Association between serum interleukin-6 concentrations and chronic obstructive pulmonary disease: a systematic review and meta-analysis

Synergistic effects of COVID-19 and Pseudomonas aeruginosa in chronic obstructive pulmonary disease: a polymicrobial perspective

This article discusses the connection between the novel coronavirus disease 2019 (COVID-19) caused by the coronavirus-2 (SARS-CoV-2) and chronic obstructive pulmonary disease (COPD). COPD is a multifaceted respiratory illness that is typically observed in individuals with chronic exposure to chemical irritants or severe lung damage caused by various pathogens, including SARS-CoV-2 and Pseudomonas aeruginosa. The pathogenesis of COPD is complex, involving a variety of genotypes and phenotypic characteristics that result in severe co-infections and a poor prognosis if not properly managed. We focus on the role of SARS-CoV-2 infection in severe COPD exacerbations in connection to P.  aeruginosa infection, covering pathogenesis, diagnosis, and therapy. This review also includes a thorough structural overview of COPD and recent developments in understanding its complicated and chronic nature. While COVID-19 is clearly linked to emphysema and chronic bronchitis at different stages of the disease, our understanding of the precise interaction between microbial infections during COPD, particularly with SARS-CoV-2 in the lungs, remains inadequate. Therefore, it is crucial to understand the host-pathogen relationship from the clinician's perspective in order to effectively manage COPD. This article aims to provide a comprehensive overview of the subject matter to assist clinicians in their efforts to improve the treatment and management of COPD, especially in light of the COVID-19 pandemic.

Nanocurcumin supplementation improves pulmonary function in severe COPD patients: A randomized, double blind, and placebo-controlled clinical trial

Considering the anti-inflammatory properties of curcumin, the present study was designed to investigate the effect of nano-curcumin on respiratory indices and interleukin-6 (IL-6) levels in severe chronic obstructive pulmonary disease (COPD) patients as a common pulmonary disease causing restricted airflow and breathing problems. In the current double-blind placebo-controlled randomized clinical trial study, 60 patients with stages 3 and 4 COPD were randomly assigned into 80 mg nano-curcumin (n = 30) and placebo groups (n = 30) for 3 months. The effect of nano-curcumin on pulmonary function was evaluated by the first second of forced expiration (FEV1) to the full, forced vital capacity (FVC) ratio. IL-6 serum level, blood pressure, and anthropometric indices were also measured. Nano-curcumin supplementation led to a significant decrease in IL-6 level (p < 0.001) and an increase in FEV1 (p < 0.001), FVC (p = 0.003), and FEV1/FVC (p < 0.001) compared to placebo at the endpoint. Nano-curcumin had a significantly increasing effect on weight and body mass index compared to the placebo group (PANCOVA adjusted for baseline values  = 0.042). There was a meaningful improvement in systolic blood pressure in the nano-curcumin group compared to the placebo group (PANCOVA adjusted for baseline values  = 0.026). There was no significant difference between the two groups in terms of waist circumference, waist-to-hip ratio, and diastolic blood pressure (PANCOVA adjusted for baseline values >0.05). Nano-curcumin supplement seems to have favorable effects on inflammation status and respiratory indices of patients with severe COPD.

Upregulated microRNA-125b-5p in patients with asthma-COPD overlap mediates oxidative stress and late apoptosis via targeting IL6R/TRIAP1 signaling

BACKGROUND

Among patients with chronic obstructive pulmonary disease (COPD), some have features of both asthma and COPD-a condition categorized as asthma-COPD overlap (ACO). Our aim was to determine whether asthma- or COPD-related microRNAs (miRNAs) play a role in the pathogenesis of ACO.

METHODS

A total of 22 healthy subjects and 27 patients with ACO were enrolled. We selected 6 miRNAs that were found to correlate with COPD and asthma. The expression of miRNAs and target genes was analyzed using quantitative reverse-transcriptase polymerase chain reaction. Cell apoptosis and intracellular reactive oxygen species production were evaluated using flow cytometry. In vitro human monocytic THP-1 cells and primary normal human bronchial epithelial (NHBE) cells under stimuli with cigarette smoke extract (CSE) or ovalbumin (OVA) allergen or both were used to verify the clinical findings.

RESULTS

We identified the upregulation of miR-125b-5p in patients with ACO and in THP-1 cells stimulated with CSE plus OVA allergen. We selected 16 genes related to the miR-125b-5p pathway and found that IL6R and TRIAP1 were both downregulated in patients with ACO and in THP-1 cells stimulated with CSE plus OVA. The percentage of late apoptotic cells increased in the THP-1 cell culture model when stimulated with CSE plus OVA, and the effect was reversed by transfection with miR-125b-5p small interfering RNA (siRNA). The percentage of reactive oxygen species-producing cells increased in the NHBE cell culture model when stimulated with CSE plus OVA, and the effect was reversed by transfection with miR-125b-5p siRNA. In NHBE cells, siRNA transfection reversed the upregulation of STAT3 under CSE+OVA stimulation.

CONCLUSIONS

Our study revealed that upregulation of miR-125b-5p in patients with ACO mediated late apoptosis in THP-1 cells and oxidative stress in NHBE cells via targeting IL6R and TRIAP1. STAT3 expression was also regulated by miR-125b-5p.

The Molecular Blueprint for Chronic Obstructive Pulmonary Disease (COPD): A New Paradigm for Diagnosis and Therapeutics

The global prevalence of chronic obstructive pulmonary disease (COPD) has increased over the last decade and has emerged as the third leading cause of death worldwide. It is characterized by emphysema with prolonged airflow limitation. COPD patients are more susceptible to COVID-19 and increase the disease severity about four times. The most used drugs to treat it show numerous side effects, including immune suppression and infection. This review discusses a narrative opinion and critical review of COPD. We present different aspects of the disease, from cellular and inflammatory responses to cigarette smoking in COPD and signaling pathways. In addition, we highlighted various risk factors for developing COPD apart from smoking, like occupational exposure, pollutants, genetic factors, gender, etc. After the recent elucidation of the underlying inflammatory signaling pathways in COPD, new molecular targeted drug candidates for COPD are signal-transmitting substances. We further summarize recent developments in biomarker discovery for COPD and its implications for disease diagnosis. In addition, we discuss novel drug targets for COPD that could be explored for drug development and subsequent clinical management of cardiovascular disease and COVID-19, commonly associated with COPD. Our extensive analysis of COPD cause, etiology, diagnosis, and therapeutic will provide a better understanding of the disease and the development of effective therapeutic options. In-depth knowledge of the underlying mechanism will offer deeper insights into identifying novel molecular targets for developing potent therapeutics and biomarkers of disease diagnosis.

Meta-analysis of single-cell RNA-sequencing data for depicting the transcriptomic landscape of chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a respiratory disease characterized by airflow limitation and chronic inflammation of the lungs that is a leading cause of death worldwide. Since the complete pathological mechanisms at the single-cell level are not fully understood yet, an integrative approach to characterizing the single-cell-resolution landscape of COPD is required. To identify the cell types and mechanisms associated with the development of COPD, we conducted a meta-analysis using three single-cell RNA-sequencing datasets of COPD. Among the 154,011 cells from 16 COPD patients and 18 healthy subjects, 17 distinct cell types were observed. Of the 17 cell types, monocytes, mast cells, and alveolar type 2 cells (AT2 cells) were found to be etiologically implicated in COPD based on genetic and transcriptomic features. The most transcriptomically diversified states of the three etiological cell types showed significant enrichment in immune/inflammatory responses (monocytes and mast cells) and/or mitochondrial dysfunction (monocytes and AT2 cells). We then identified three chemical candidates that may potentially induce COPD by modulating gene expression patterns in the three etiological cell types. Overall, our study suggests the single-cell level mechanisms underlying the pathogenesis of COPD and may provide information on toxic compounds that could be potential risk factors for COPD.

ACE2 and a Traditional Chinese Medicine Formula NRICM101 Could Alleviate the Inflammation and Pathogenic Process of Acute Lung Injury

COVID-19 is a highly transmittable respiratory illness caused by SARS-CoV-2, and acute lung injury (ALI) is the major complication of COVID-19. The challenge in studying SARS-CoV-2 pathogenicity is the limited availability of animal models. Therefore, it is necessary to establish animal models that can reproduce multiple characteristics of ALI to study therapeutic applications. The present study established a mouse model that has features of ALI that are similar to COVID-19 syndrome to investigate the role of ACE2 and the administration of the Chinese herbal prescription NRICM101 in ALI. Mice with genetic modifications, including overexpression of human ACE2 (K18-hACE2 TG) and absence of ACE2 (mACE2 KO), were intratracheally instillated with hydrochloric acid. The acid intratracheal instillation induced severe immune cell infiltration, cytokine storms, and pulmonary disease in mice. Compared with K18-hACE2 TG mice, mACE2 KO mice exhibited dramatically increased levels of multiple inflammatory cytokines (IL-6 and TNF-α) in bronchoalveolar lavage fluid, histological evidence of lung injury, and dysregulation of MAPK and MMP activation. In mACE2 KO mice, NRICM101 could ameliorate the disease progression of acid-induced ALI. In conclusion, the established mouse model provided an effective platform for researchers to investigate pathological mechanisms and develop therapeutic strategies for ALI, including COVID-19-related ALI.

Explore bioactive ingredients and potential mechanism of Houpo Mahuang decoction for chronic bronchitis based on UHPLC-Q exactive orbitrap HRMS, network pharmacology, and experiment verification

ETHNOPHARMACOLOGICAL RELEVANCE

Chronic bronchitis (CB) affects a growing number of people and may be linked to lung function impairment. The traditional Chinese medicine formula Houpo Mahuang Decoction (HPMHD) has been used for clinical treatment of respiratory diseases for thousands of years. Until now, its bioactive ingredients, potential targets and molecular mechanism remain unclear.

AIM OF THE STUDY

To investigate the effect of HPMHD on the treatment of CB and explore the bioactive ingredients and possible mechanisms of HPMHD against CB.

MATERIALS AND METHODS

UHPLC-Q Exactive Orbitrap HRMS was performed to analyze the chemical components of HPMHD. The mechanism of multiple components, targets and pathways of HPMHD in the treatment of chronic bronchitis were explored by network pharmacology. Additionally, CB mice model induced by lipopolysaccharide (LPS) and smoking was used to evaluate the anti-chronic bronchitis activity of HPMHD in vivo. Pulmonary pathology was determined by hematoxylin and eosin (H&E) measurement. The levels of TNF-α and IL-6 in lung were measured by ELISA. The immunofluorescence experiments were carried out for the expression of IL-1β, TNF-α, IL-6 and NF-κB p-P65/P65 in lung. Western blot assays were performed to quantify and visualize the protein expression of NF-κB p-P65/P65 in mice lung.

RESULTS

Data showed that 79 compounds were identified in HPMHD. The network pharmacology results showed 53 compounds were hinted their effectivity for the treatment of chronic bronchitis with HPMHD, such as ephedrine, schisantherin A, and honokiol. The main targets were predicted as 37 genes, including TNF, TP53, IL6 and so on. HPMHD ameliorated lung damages in mice and inhibited the NF-κB signaling pathway, one of the pathways plotted by KEGG pathway enrichment analysis, by reducing IL-1β, TNF-α and IL-6 expression and significantly downregulating the NF-κB p-P65/P65.

CONCLUSION

In summary, the complex chemical components of HPHMD was successfully elucidate by UHPLC-Q Exactive Orbitrap HRMS. The study based on network pharmacology and experiment verification indicated that HPMHD can decreased inflammatory response in lung to treat CB. The underlying mechanism may be related to the reduction of inflammation by down-regulated the NF-κB pathways.

Impaired muscle stem cell function and abnormal myogenesis in acquired myopathies

Skeletal muscle possesses a high plasticity and a remarkable regenerative capacity that relies mainly on muscle stem cells (MuSCs). Molecular and cellular components of the MuSC niche, such as immune cells, play key roles to coordinate MuSC function and to orchestrate muscle regeneration. An abnormal infiltration of immune cells and/or imbalance of pro- and anti-inflammatory cytokines could lead to MuSC dysfunctions that could have long lasting effects on muscle function. Different genetic variants were shown to cause muscular dystrophies that intrinsically compromise MuSC function and/or disturb their microenvironment leading to impaired muscle regeneration that contributes to disease progression. Alternatively, many acquired myopathies caused by comorbidities (e.g., cardiopulmonary or kidney diseases), chronic inflammation/infection, or side effects of different drugs can also perturb MuSC function and their microenvironment. The goal of this review is to comprehensively summarize the current knowledge on acquired myopathies and their impact on MuSC function. We further describe potential therapeutic strategies to restore MuSC regenerative capacity.

Ultra-Sensitive and Semi-Quantitative Vertical Flow Assay for the Rapid Detection of Interleukin-6 in Inflammatory Diseases

The inflammation biomarker Interleukin 6 (IL-6) exhibits a concentration of less than 7 pg/mL in healthy serum but increases 10–100-fold when inflammation occurs. Increased serum IL-6 has been reported in chronic diseases such as rheumatoid arthritis (RA), as well as in life-threatening acute illnesses such as sepsis and cytokine release syndrome (CRS). This work seeks to meet the demand for rapid detection of serum IL-6 both for rapid monitoring of chronic diseases and for triaging patients with acute illnesses. Following the optimization of several types of gold nanoparticles, membrane pore sizes, and buffer systems, an ultra-sensitive vertical flow assay (VFA) was engineered, allowing the detection of recombinant IL-6 in spiked buffer with a limit of detection (LoD) of 10 pg/mL and a reportable range of 10–10,000 pg/mL with a 15-min assay time. The detection of IL-6 in spiked pooled healthy serum exhibited an LoD of 3.2 pg/mL and a reportable range of 10–10,000 pg/mL. The VFA’s stability was demonstrated over 1-day, two-week, four-week, and six-week storage durations at room temperature. The inter-operator CV and intra-operator CV were determined to be 14.3% and 15.2%, respectively. Three reference zones, high, low, and blank, were introduced into the cartridge to facilitate on-site semi-quantitative measurements across a 6-point semi-quantitative range. Finally, the performance of the IL-6 VFA was validated using 20 RA and 20 healthy control (HC) clinical serum samples, using ELISA as the gold standard platform. The ultra-sensitive, rapid IL-6 VFA could potentially be used to triage patients for intensive care, treatment adjustments, or for monitoring disease activity in inflammatory conditions.

Healthy Sleep Every Day Keeps the Doctor Away

When one considers the big picture of their health, sufficient sleep may often go overlooked as a keystone element in this picture. Insufficient sleep in either quality or duration is a growing problem for our modern society. It is essential to look at what this means for our health because insufficient sleep increases our risks of innumerable lifechanging diseases. Beyond increasing the risk of developing these diseases, it also makes the symptoms and pathogenesis of many diseases worse. Additionally, consistent quality sleep can not only improve our physical health but has also been shown to improve mental health and overall quality of life. Substandard sleep health could be a root cause for numerous issues individuals may be facing in their lives. It is essential that physicians take the time to learn about how to educate their patients on sleep health and try to work with them on an individual level to help motivate lifestyle changes. Facilitating access to sleep education for their patients is one way in which physicians can help provide patients with the tools to improve their sleep health. Throughout this paper, we will review the mechanisms behind the relationship between insufficient sleep health and chronic disease and what the science says about how inadequate sleep health negatively impacts the overall health and the quality of our lives. We will also explain the lifechanging effects of sufficient sleep and how we can help patients get there.

Artemisia gmelinii Attenuates Lung Inflammation by Suppressing the NF-κB/MAPK Pathway

Cigarette smoke (CS) is the main cause of chronic obstructive pulmonary disease (COPD), and continuous CS exposure causes lung inflammation and deterioration. To investigate the protective effects of Artemisia gmelinii against lung inflammation in this study, cigarette smoke extract (CSE)/lipopolysaccharide (LPS)-treated alveolar macrophages (AMs) and mice stimulated with CSE/porcine pancreas elastase (PPE) were used. Artemisia gmelinii ethanol extract (AGE) was effective in decreasing the levels of cytokines, chemokine, inducible nitric oxide synthase, and cyclooxygenase-2 by inhibiting mitogen-activated protein (MAP) kinases/nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling pathway in AMs. Additionally, oral administration of AGE suppressed inflammatory cells’ infiltration and secretion of inflammatory cytokines, chemokines, matrix metallopeptidase 9, and neutrophil extracellular traps in bronchoalveolar lavage fluid from the COPD model. Moreover, the obstruction of small airways, the destruction of the lung parenchyma, and expression of IL-6, TNF-α, IL-1β, and MIP-2 were suppressed by inhibiting NF-κB activation in the lung tissues of the AGE group. These effects are associated with scopolin, chlorogenic acid, hyperoside, 3,4-di-O-caffeoylquinic acid, 3,5-di-O-caffeoylquinic acid, and 4,5-di-O-caffeoylquinic acid, which are the main components of AGE. These data demonstrate the mitigation effect of AGE on lung inflammation via inhibition of MAPK and NF-κB pathways, suggesting that AGE may be instrumental in improving respiratory and lung health.

Altered Differentiation and Inflammation Profiles Contribute to Enhanced Innate Responses in Severe COPD Epithelium to Rhinovirus Infection

Background

Respiratory viral infections are closely associated with COPD exacerbations, hospitalisations, and significant morbidity and mortality. The consequences of the persisting inflammation and differentiation status in virus associated severe disease is not fully understood. The aim of this study was to evaluate barrier function, cellular architecture, the inflammatory response in severe COPD bronchial epithelium to human rhinovirus (HRV) induced pathological changes and innate immune responses.

Methods

Well-differentiated primary bronchial epithelial cells (WD-PBECs) derived from severe COPD patients and age-matched healthy controls were cultured in the air-liquid interface (ALI) model. The differentiation phenotype, epithelial barrier integrity, pathological response and cytokine secreting profile of these cultures before and after HRV infection were investigated.

Results

WD-PBECs derived from severe COPD patients showed aberrant epithelium differentiation with a decreased proportion of ciliated cells but increased numbers of club cells and goblet cells compared with healthy controls. Tight junction integrity was compromised in both cultures following HRV infection, with heightened disruptions in COPD cultures. HRV induced increased epithelial cell sloughing, apoptosis and mucus hypersecretion in COPD cultures compared with healthy controls. A Th1/Th2 imbalance and a strong interferon and pro-inflammatory cytokine response was also observed in COPD cultures, characterized by increased levels of IFNγ, IFNβ, IP-10, IL-10 and decreased TSLP and IL-13 cytokine levels prior to HRV infection. Significantly enhanced basolateral secretion of eotaxin 3, IL-6, IL-8, GM-CSF were also observed in both mock and HRV infected COPD cultures compared with corresponding healthy controls. In response to HRV infection, all cultures displayed elevated levels of IFNλ1 (IL-29), IP-10 and TNFα compared with mock infected cultures. Interestingly, HRV infection dramatically reduced IFNλ levels in COPD cultures compared with healthy subjects.

Conclusion

An altered differentiation phenotype and cytokine response as seen in severe COPD WD-PBECs may contribute to increased disease susceptibility and an enhanced inflammatory response to HRV infection.

Role of interluekin-6 and insulin resistance as screening markers for metabolic syndrome in patients of chronic obstructive pulmonary disease. A hospital based cross-sectional study

Chronic obstructive pulmonary disease (COPD) is usually associated with a variety of extra-pulmonary manifestations. Metabolic syndrome (MetS) is one such entity that has been scarcely studied in Indian patients. Availability of a good screening marker may help in timely detection of this co morbidity in COPD patients. We conducted a cross sectional study to evaluate the prevalence of MetS among COPD patients and to evaluate the role of Interleukin-6 and insulin resistance (as measured by HOMA-IR) as screening markers for MetS in COPD. A total of 100 stable COPD patients were evaluated for MetS using US National Cholesterol Education Program Adult Treatment Panel III (2005) guidelines. Interleukin-6 and HOMA-IR (for insulin resistance) were measured and compared between COPD patients with and without MetS. ROC analysis was done to find the best cut-off value and sensitivity and specificity of both the molecules in detecting MetS. In the results, the mean age of the study cohort was 59.9+8.7yrs (males=93). Forty five COPD patients (45%) fulfilled the criteria for MetS. Patients with MetS were comparatively younger (57.9+9.5 v/s 61.6+7.8 years; p=0.037) but had longer duration of preceding COPD (9.9+2.8 v/s 6.0+2.2 years; p<0.001) as compared to those without MetS. Both IL-6 and HOMA index were statistically higher (p<0.05) in COPD-MetS patients as compared to the other group. At cutoff value of 36.3 pg/ml for IL-6 and 1.61 for HOMA index, IL-6 and HOMA-IR had sensitivity 91.1% and 82.2% respectively in detecting MetS among COPD patients. To conclude, metabolic syndrome is a common comorbidity seen in COPD patients. Interleukin-6 has a better sensitivity than HOMA-IR in screening MetS among COPD patients.

Health impacts of a randomized biomass cookstove intervention in northern Ghana

BACKGROUND

Household air pollution (HAP) from cooking with solid fuels has adverse health effects. REACCTING (Research on Emissions, Air quality, Climate, and Cooking Technologies in Northern Ghana) was a randomized cookstove intervention study that aimed to determine the effects of two types of "improved" biomass cookstoves on health using self-reported health symptoms and biomarkers of systemic inflammation from dried blood spots for female adult cooks and children, and anthropometric growth measures for children only.

METHODS

Two hundred rural households were randomized into four different cookstove groups. Surveys and health measurements were conducted at four time points over a two-year period. Chi-square tests were conducted to determine differences in self-reported health outcomes. Linear mixed models were used to assess the effect of the stoves on inflammation biomarkers in adults and children, and to assess the z-score deviance for the anthropometric data for children.

RESULTS

We find some evidence that two biomarkers of oxidative stress and inflammation, serum amyloid A and C-reactive protein, decreased among adult primary cooks in the intervention groups relative to the control group. We do not find detectable impacts for any of the anthropometry variables or self-reported health.

CONCLUSIONS

Overall, we conclude that the REACCTING intervention did not substantially improve the health outcomes examined here, likely due to continued use of traditional stoves, lack of evidence of particulate matter emissions reductions from "improved" stoves, and mixed results for HAP exposure reductions.

CLINICAL TRIAL REGISTRY

ClinicalTrials.gov (National Institutes of Health); Trial Registration Number: NCT04633135 ; Date of Registration: 11 November 2020 - Retrospectively registered. URL: https://clinicaltrials.gov/ct2/show/NCT04633135?term=NCT04633135&draw=2&rank=1.

Circulating C-reactive protein levels in patients with suspected obstructive sleep apnea

STUDY OBJECTIVES

To assess determinants of CRP in a cohort of patients referred for investigation of OSA and to determine whether overlap of OSA and COPD (overlap syndrome, OVS) is associated with higher levels of CRP.

METHODS

This was a cross-sectional study that included 2352 patients seen at the West Australian Sleep Disorders Research Institute between 2006 and 2010. All patients had circulating CRP levels, and spirometry performed. OSA was defined apnea-hypopnea index (AHI) ≥ 5 events per hour and COPD defined as FEV1/FVC ratio <0.70 and age > 40 years. Univariate and multivariate regression analysis were used to identify CRP determinants.

RESULTS

Mean age was 51 years (60% male), median (AHI) was 27 events/h, median 3% oxygen desaturation index (ODI3%) was 24 events/h, mean FEV₁ was 88% predicted, and median CRP was 3.0 mg/L. In multivariate analyses: age, body mass index, female sex, neck circumference, AHI, and desaturation markers (nadir and mean oxygen saturation) were independently associated with higher CRP. Spirometric variables were not predictors. There was no significant difference in CRP among OSA patients with or without co-existing COPD.

CONCLUSIONS

Markers of OSA severity (AHI and oxygenation), age, BMI, neck circumference and female sex were independent predictors of circulating CRP levels. OSA overlapping with COPD was not associated with increased CRP compared to either condition alone, suggesting other mechanisms for the increased CVD risk in OVS. Identification of factors that predict CRP will help identify patients at higher risk of CVD and aid risk stratification.

Nine-Year Follow-Up of Interleukin 6 in Chronic Obstructive Pulmonary Disease - Complementary Results from Previous Studies

Background

Systemic manifestations of chronic obstructive pulmonary disease (COPD) are related to increased systemic inflammatory process; however, it is not entirely clear how much they are related and how the systemic inflammation, in particular interleukin-6 (IL-6), is associated with exacerbation and mortality risk.

Objective

To evaluate the role of IL-6 in COPD patients over nine years.

Study Design and Methods

A total of 133 COPD patients were assessed at baseline between 2004 and 2006 and reassessed after three and nine years through clinical evaluation, comorbidities, hematological blood count and IL-6 analysis.

Results

After nine years, 19 patients lost the follow-up and were not possible to identify the date of death of four patients; 12 refused to participate and 1 could not be involved due to recurrent exacerbations. Therefore, 33 patients were included in the reassessment after nine years of follow-up and 92 patients were included in the Cox mortality analysis with IL-6 as a time-dependent covariate. Regarding the inflammatory profile, in patients who survived after nine years, there was a significant increase in IL-6 [0.4 (0.2–0.8) vs 5.7 (3.4–11) pg/mL; p < 0.001] and reduction in lymphocyte count [2.1 (1.6–2.4) vs 1.4 (1.2–2.1)10^9/L; p < 0.01] with an increase in the neutrophil/lymphocyte ratio (2.0 ± 0.7 vs 2.7 ± 1.2; p = 0.003). The Cox mortality model did not show a statistical significance influence of IL-6 assessed during the follow-up.

Conclusion

There was a progressive increase in IL-6 during the follow-up, however, without influence on mortality.

Chronic Obstructive Pulmonary Disease and Its Acute Exacerbation before Colon Adenocarcinoma Treatment Are Associated with Higher Mortality: A Propensity Score-Matched, Nationwide, Population-Based Cohort Study

Simple Summary

This is the first study to reveal that hospitalization frequency for acute exacerbation of chronic obstructive pulmonary disease (AECOPD) before colon adenocarcinoma treatment is a severity-dependent and independent prognostic factor for overall survival in patients with stage I–III colon cancer receiving surgical resection and standard treatments. In patients with colon adenocarcinoma undergoing curative resection, those with chronic obstructive pulmonary disease (COPD) had poorer survival outcomes than had those without COPD. Hospitalization for AECOPD at least once within 1 year before colon adenocarcinoma diagnosis is an independent risk factor for poor overall survival in these patients, and a higher number of hospitalizations for AECOPD within 1 year before diagnosis was associated with poorer survival. Our study may be applied to accentuate the importance of COPD management, particularly the identification of frequent exacerbators and the prevention of AECOPD, before standard colon adenocarcinoma treatments are initiated.

Abstract

Purpose: To investigate whether chronic obstructive pulmonary disease (COPD) and COPD severity (acute exacerbation of COPD (AECOPD)) affect the survival outcomes of patients with colon adenocarcinoma receiving standard treatments. Methods: From the Taiwan Cancer Registry Database, we recruited patients with clinical stage I–III colon adenocarcinoma who had received surgery. The Cox proportional hazards model was used to analyze all-cause mortality. We categorized the patients into COPD and non-COPD (Group 1 and 2) groups through propensity score matching. Results: In total, 1512 patients were eligible for further comparative analysis between non-COPD (1008 patients) and COPD (504 patients) cohorts. In the multivariate Cox regression analysis, the adjusted hazard ratio (aHR; 95% confidence interval (CI)) for all-cause mortality for Group 1 compared with Group 2 was 1.17 (1.03, 1.29). In patients with colon adenocarcinoma undergoing curative resection, the aHRs (95% CIs) for all-cause mortality in patients with hospitalization frequencies of ≥1 and ≥2 times for AECOPD within 1 year before adenocarcinoma diagnosis were 1.08 (1.03, 1.51) and 1.55 (1.15, 2.09), respectively, compared with those without AECOPD. Conclusion: In patients with colon adenocarcinoma undergoing curative resection, COPD was associated with worse survival outcomes. Being hospitalized at least once for AECOPD within 1 year before colon adenocarcinoma diagnosis was an independent risk factor for poor overall survival in these patients, and a higher number of hospitalizations for AECOPD within 1 year before diagnosis was associated with poorer survival. Our study highlights the importance of COPD management, particularly the identification of frequent exacerbators and the prevention of AECOPD before standard colon adenocarcinoma treatments are applied.

Association of Systemic Inflammation with Depressive Symptoms in Individuals with COPD

Rationale

Depression is a prevalent comorbidity of chronic obstructive pulmonary disease (COPD) that, along with COPD, has been associated with inflammation. An association between inflammation and depression in COPD has not been validated in a large COPD cohort.

Methods

Individuals from the University of Pittsburgh SCCOR cohort and the COPDGene cohort with tobacco use history and airway obstruction (FEV₁/FVC <0.7) were evaluated using the Beck Depression Inventory II (BDI-II) and the Hospital Anxiety and Depression Scale (HADS), respectively. Participants completed symptom-related questionnaires and plasma IL-6 measurements. T-test, Fisher’s Exact tests and logistic regression were used for statistical analysis.

Results

The SCCOR cohort included 220 obstructed participants: 44% female and 21.4% with elevated depressive symptoms. GOLD staging distribution was predominantly stage I and II. The COPDGene cohort included 745 obstructed participants: 44% female and 13.0% with elevated depressive symptoms. GOLD distribution was predominantly stage II and III. In the SCCOR cohort, correlation between IL-6 and depressive symptoms trended toward significance (p= 0.08). Multivariable modeling adjusted for FEV₁, age, gender and medical comorbidities showed a significant association (OR = 1.70, 95% CI = 1.08–2.69). IL-6 was significantly associated with elevated depressive symptoms in COPDGene in both univariate (p=0.001) and multivariable modeling (OR = 1.52, 95% CI =1.13–2.04).

Conclusion

Elevated plasma IL-6 levels are associated with depressive symptoms in individuals with COPD independent of airflow limitation and comorbid risk factors for depression. Our results suggest that systemic inflammation may play a significant and possibly bidirectional role in depression associated with COPD.

HDAC6 Activates ERK in Airway and Pulmonary Vascular Remodeling of COPD

Chronic obstructive pulmonary disease (COPD) is a multisystemic respiratory disease which is associated with progressive airway and pulmonary vascular remodeling due to the increased proliferation of bronchial and pulmonary arterial smooth muscle cells (BSMCs and PASMCs) and overproduction of extracellular matrix (ECM), e.g., collagen. Cigarette smoke (CS) and several mediators such as PDGF and IL-6 play critical role in the COPD pathogenesis. Histone deacetylase 6 (HDAC6) has been shown to be implicated in vascular remodeling. However, the HDAC6 signaling in airway and pulmonary vascular remodeling of COPD and the underlying mechanisms remain undetermined. Here we show that HDAC6 expression is upregulated in lungs of COPD patients and animal model. We also found that cigarette smoke extract (CSE), PDGF and IL-6 increase the protein levels and activation of HDAC6 in BSMCs and PASMCs. Furthermore, CSE and these stimulants induced deacetylation and phosphorylation of ERK1/2 and increased collagen synthesis and proliferation of BSMCs and PASMCs which were prevented by HDAC6 inhibition. Inhibition of ERK1/2 also diminished the CSE, PDGF and IL-6-caused elevation in collagen levels and cell proliferation. Pharmacological HDAC6 inhibition by tubastatin A prevented the CS-stimulated increases in the thickness of the bronchial and pulmonary arterial wall, airway resistance, emphysema as well as right ventricular (RV) systolic pressure (RVSP) and RV hypertrophy in rat model of COPD. These data demonstrate that the upregulated HDAC6 governs the collagen synthesis and proliferation of BSMCs and PASMCs leading to airway and vascular remodeling in COPD.

Etanercept Protected Against Cigarette Smoke Extract-Induced Inflammation and Apoptosis of Human Pulmonary Artery Endothelial Cells via Regulating TNFR1

Purpose

Etanercept (ETN), a tumor necrosis factor-α (TNF-α) inhibitor, has been applied in the treatment of many diseases. However, whether it has effects on chronic obstructive pulmonary disease (COPD) and its interaction with tumor necrosis factor receptor 1 (TNFR1) remained unknown.

Methods

Histopathological analysis of lung tissues from non-smokers and smokers with or without COPD was conducted using hematoxylin–eosin (H&E) staining, Van Gieson (VG) staining, and terminal transferase-mediated biotin dUTP nick end labeling (TUNEL). TNF-α content was measured using Immunohistochemistry. Correlation analysis among apoptosis rate, smoke index, the FEV1/FVC ratio, and TNF-α-positive cells was performed. After ETN treatment and transfection of overexpressed or silenced TNFR1, levels of inflammatory cytokines, apoptosis and related genes expressions in cigarette smoke extract (CSE)-treated human pulmonary artery endothelial cells (HPAECs) were detected using enzyme-linked immunosorbent assay (ELISA), Hoechst 33342 staining, flow cytometry, quantitative real-time PCR (qRT-PCR) and Western blot.

Results

Pulmonary arterial remodeling and increased apoptotic and TNF-α⁺ HPAECs were found in lung tissue of smokers with or without COPD, with higher degrees in smokers with COPD. The numbers of apoptotic and TNF-α⁺ HPAECs were positively correlated with smoke index, while the FEV1/FVC ratio was negatively correlated with apoptotic HPAECs. In HPAECs, ETN downregulated the expressions of proteins related to CSE-induced apoptosis and the TNF receptor family, decreased CSE-induced cell apoptosis and inflammatory cytokine levels, and inhibited TNFR1 expression and p65 phosphorylation. Overexpressed TNFR1 reversed the effects of ETN on CSE-treated HPAECs, whereas silencing TNFR1 did the opposite.

Conclusion

ETN protected HPAECs against CSE-induced inflammation and apoptosis via downregulating TNFR1, thus providing a potential therapy for smoking-induced COPD.

IL-6 family cytokines in respiratory health and disease

Chronic lung diseases including asthma, chronic obstructive pulmonary disease (COPD) and lung fibrosis represent a major burden on healthcare systems with limited effective therapeutic options. Developing effective treatments for these debilitating diseases requires an understanding of how alterations at the molecular level affect lung macroscopic architecture. A common theme among these lung disorders is the presence of an underlying dysregulated immune system which can lead to sustained chronic inflammation. In this respect, several inflammatory cytokines have been implicated in the pathogenesis of lung diseases, thus leading to the notion that cytokines are attractive therapeutic targets for these disorders. In this review, we discuss and highlight the recent breakthroughs that have enhanced our understanding of the role of the interleukin (IL)-6 family of cytokines in lung homeostasis and chronic diseases including asthma, COPD, lung fibrosis and lung cancer.

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

Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality worldwide and encompasses chronic bronchitis and emphysema. It has been shown that vascular wall remodeling and pulmonary hypertension (PH) can occur not only in patients with COPD but also in smokers with normal lung function, suggesting a causal role for vascular alterations in the development of emphysema. Mechanistically, abnormalities in the vasculature, such as inflammation, endothelial dysfunction, imbalances in cellular apoptosis/proliferation, and increased oxidative/nitrosative stress promote development of PH, cor pulmonale, and most probably pulmonary emphysema. Hypoxemia in the pulmonary chamber modulates the activation of key transcription factors and signaling cascades, which propagates inflammation and infiltration of neutrophils, resulting in vascular remodeling. Endothelial progenitor cells have angiogenesis capabilities, resulting in transdifferentiation of the smooth muscle cells via aberrant activation of several cytokines, growth factors, and chemokines. The vascular endothelium influences the balance between vaso-constriction and -dilation in the heart. Targeting key players affecting the vasculature might help in the development of new treatment strategies for both PH and COPD. The present review aims to summarize current knowledge about vascular alterations and production of reactive oxygen species in COPD. The present review emphasizes on the importance of the vasculature for the usually parenchyma-focused view of the pathobiology of COPD.

Plasma proteomics and lung function in four community-based cohorts

BACKGROUND

Underlying mechanism leading to impaired lung function are incompletely understood.

OBJECTIVES

To investigate whether protein profiling can provide novel insights into mechanisms leading to impaired lung function.

METHODS

We used four community-based studies (n = 2552) to investigate associations between 79 cardiovascular/inflammatory proteins and forced expiratory volume in 1 s percent predicted (FEV₁%) assessed by spirometry. We divided the cohorts into discovery and replication samples and used risk factor-adjusted linear regression corrected for multiple comparison (false discovery rate of 5%). We performed Mendelian randomization analyses using genetic and spirometry data from the UK Biobank (n = 421,986) to assess causality.

MEASUREMENTS AND MAIN RESULTS

In cross-sectional analysis, 22 proteins were associated with lower FEV₁% in both the discovery and replication sample, regardless of stratification by smoking status. The combined proteomic data cumulatively explained 5% of the variation in FEV₁%. In longitudinal analyses (n = 681), higher plasma levels of growth differentiation factor 15 (GDF-15) and interleukin 6 (IL-6) predicted a more rapid 5-year decline in lung function (change in FEV₁% per standard deviation of protein level -1.4, (95% CI, -2.5 to -0.3) for GDF-15, and -0.8, (95% CI, -1.5 to -0.2) for IL-6. Mendelian randomization analysis in UK-biobank provided support for a causal effect of increased GDF-15 levels and reduced FEV₁%.

CONCLUSIONS

Our combined approach identified GDF-15 as a potential causal factor in the development of impaired lung function in the general population. These findings encourage additional studies evaluating the role of GDF-15 as a causal factor for impaired lung function.

SARS-CoV-2 spike protein promotes IL-6 trans-signaling by activation of angiotensin II receptor signaling in epithelial cells

Cytokine storm is suggested as one of the major pathological characteristics of SARS-CoV-2 infection, although the mechanism for initiation of a hyper-inflammatory response, and multi-organ damage from viral infection is poorly understood. In this virus-cell interaction study, we observed that SARS-CoV-2 infection or viral spike protein expression alone inhibited angiotensin converting enzyme-2 (ACE2) receptor protein expression. The spike protein promoted an angiotensin II type 1 receptor (AT1) mediated signaling cascade, induced the transcriptional regulatory molecules NF-κB and AP-1/c-Fos via MAPK activation, and increased IL-6 release. SARS-CoV-2 infected patient sera contained elevated levels of IL-6 and soluble IL-6R. Up-regulated AT1 receptor signaling also influenced the release of extracellular soluble IL-6R by the induction of the ADAM-17 protease. Use of the AT1 receptor antagonist, Candesartan cilexetil, resulted in down-regulation of IL-6/soluble IL-6R release in spike expressing cells. Phosphorylation of STAT3 at the Tyr705 residue plays an important role as a transcriptional inducer for SOCS3 and MCP-1 expression. Further study indicated that inhibition of STAT3 Tyr705 phosphorylation in SARS-CoV-2 infected and viral spike protein expressing epithelial cells did not induce SOCS3 and MCP-1 expression. Introduction of culture supernatant from SARS-CoV-2 spike expressing cells on a model human liver endothelial Cell line (TMNK-1), where transmembrane IL-6R is poorly expressed, resulted in the induction of STAT3 Tyr705 phosphorylation as well as MCP-1 expression. In conclusion, our results indicated that the presence of SARS-CoV-2 spike protein in epithelial cells promotes IL-6 trans-signaling by activation of the AT1 axis to initiate coordination of a hyper-inflammatory response.

Combination of Systemic Inflammatory Biomarkers in Assessment of Chronic Obstructive Pulmonary Disease: Diagnostic Performance and Identification of Networks and Clusters

Interleukin (IL)-1α, IL-1β, IL-6, IL-8 and tumor necrosis factor (TNF)α contribute to inflammation in chronic obstructive pulmonary disease (COPD). We wanted to investigate their interrelations and association with disease severity, as well as to combine them with other inflammation-associated biomarkers and evaluate their predictive value and potential in identifying various patterns of systemic inflammation. One hundred and nine patients with stable COPD and 95 age- and sex-matched controls were enrolled in the study. Cytokines’ concentrations were determined in plasma samples by antibody-based multiplex immunosorbent assay kits. Investigated cytokines were increased in COPD patients but were not associated with disease or symptoms severity. IL-1β, IL-6 and TNFα showed the best discriminative values regarding ongoing inflammation in COPD. Inflammatory patterns were observed in COPD patients when cytokines, C-reactive protein (CRP), fibrinogen (Fbg), extracellular adenosine triphosphate (eATP), extracellular heat shock protein 70 (eHsp70) and clinical data were included in cluster analysis. IL-1β, eATP and eHsp70 combined correctly classified 91% of cases. Therefore, due to the heterogeneity of COPD, its assessment could be improved by combination of biomarkers. Models including IL-1β, eATP and eHsp70 might identify COPD patients, while IL-1β, IL-6 and TNFα combined with CRP, Fbg, eATP and eHsp70 might be informative regarding various COPD clinical subgroups.

Long-term dietary fiber intake and risk of chronic obstructive pulmonary disease: a prospective cohort study of women

PURPOSE

Until now, only two prospective cohort studies have investigated dietary fiber intake in relation to risk of chronic obstructive pulmonary disease (COPD), but neither examined long-term fiber intake. Both studies reported that total fiber intake was associated with decreased COPD risk; however, results for specific fiber sources were inconsistent. Thus, we prospectively evaluated the association between baseline and long-term intake of dietary fiber and COPD risk in a population-based prospective cohort of 35,339 Swedish women.

METHODS

Dietary fiber intake was assessed in 1987 and 1997 with a food frequency questionnaire. Cox proportional hazard regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

During follow-up (2002-2014), 1557 COPD cases were identified via linkage to the Swedish National Patient Register. Long-term high dietary fiber intake (≥ 26.5 vs. < 17.6 g/day) was associated with a 30% (95% CI 17-41%) lower risk of COPD. For specific fiber sources, cereal (≥ 16.3 vs. < 9.4 g/day; HR 0.67, 95% CI 0.55-0.81) and fruit fiber (≥ 7.6 vs. < 2.6 g/day; HR 0.65, 95% CI 0.5-0.81), but not vegetable fiber intake (≥ 5.4 vs. < 2.2 g/day; HR 1.03, 95% CI 0.81-1.28) were associated with lower COPD risk. Current and ex-smokers with low long-term total fiber intake (< 17.6 g/day) compared to never smokers with high intake (≥ 26.5 g/day) had a 33-fold (95% CI 23.6-46.6) and tenfold (95% CI 7.0-16.3), respectively, higher risk of COPD.

CONCLUSIONS

Our findings indicate that high fiber intake is a modifiable lifestyle factor which may decrease COPD risk primarily in current and ex-smokers.

Pulmonary functions in children and adolescents with sickle cell disease

BACKGROUND

Sickle cell disease (SCD) is relatively common in Bahrain, and airway inflammation in patients with SCD is usually multifactorial. This study aimed to evaluate lung function and induced sputum levels of interleukin-6 (IL-6) in Bahraini children and adolescents with SCD and assess their relationship with the recurrence of acute chest syndrome (ACS).

METHODS

A total of 139 children and adolescents with SCD and 123 healthy children (control group) were included in the present study. Patients were further stratified according to age and history of ACS. The patient and control groups underwent pulmonary function tests (PFTs), including spirometry and assessments of lung volume, diffusion of carbon monoxide (DLCO), and induced sputum IL-6 levels.

RESULTS

Forced expiratory volume in 1 second (FEV₁ ), force vital capacity (FVC), FEV₁ /FVC, total lung capacity, DLCO, and DLCOc (ie, hemoglobin-corrected DLCO) were significantly lower, while residual volume and sputum IL-6 levels were significantly higher in the patient group than in the control group. PFT parameters were more compromised in the patient subgroup with a history of ACS and older than 12 years compared with the subgroup without a history of ACS and the subgroup under 12 years of age. PFTs revealed significant negative correlations with age, number of ACS events, and sputum IL-6 levels.

CONCLUSION

Pulmonary function was observed to worsen with disease progression, and it worsened with older age and repeated occurrence of ACS. Induced sputum IL-6 levels reflected the degree of lung inflammation in affected patients and were associated with more impairment in various PFT parameters.

Features of cytokine signaling forming T-helper immune response in COPD of varying severity

Introduction — Currently, chronic obstructive pulmonary disease (COPD) is a global public health problem. However, molecular mechanisms of the development of this pathology are still poorly understood. The aim is to establish mechanisms of cytokine regulation of T-helper (Th) immune pathway in patients with COPD of varying severity. Material and Methods — The study included 112 patients with stable COPD (mild, moderate and severe grade) and 32 healthy volunteers (control group). We investigated serum cytokine levels (tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), interleukin 4 (IL-4), IL-6, IL-10, IL-17A) and the percentage of circulating Th cells (CD4+) expressing membrane receptor to IL-6 (IL-6R or CD126+), using flow cytometry. The levels of transforming growth factor-β1 (TGF-β1) and IL-21 were detected by ELISA. The direction of immune response in COPD patients was determined depending on the prevalence of cytokines playing a crucial role in the formation of certain Th cells type (Th1, Th17). Results — Th1-associated cytokine profile was expressed at the initial stage of COPD; the Th17-associated cytokine profile begins to prevail at severe COPD. Among COPD patients with Th1-associated cytokine profile, a statistically significant increase in the number of CD4+CD126+ cells in comparison with the control group was identified only in severe COPD. In the group of COPD patients with Th17-associated cytokine profile, an increase in the number of CD4+CD126+ cells were observed at all severity stages of the pathology. Conclusion — Moderate and severe COPD are characterized by the predominance of Th17-associated cytokine profile leading to chronic inflammation. The increase in IL-6R expression levels in circulating CD4+ cells serves as the mechanism for enhancing Th17-associated response in COPD.

GTS-21, an α7nAChR agonist, suppressed the production of key inflammatory mediators by PBMCs that are elevated in COPD patients and associated with impaired lung function

Chronic obstructive pulmonary disease (COPD) is a lung inflammatory disease characterized by progressive airflow limitation, chronic respiratory symptoms and frequent exacerbations. There is an unmet need to identify novel therapeutic alternatives beside bronchodilators that prevent disease progression. Levels of both Nitric Oxide (NO) and IL-6 were significantly increased in the plasma of patients in the exacerbation phase (ECOPD, n = 13) when compared to patients in the stable phase (SCOPD, n = 38). Levels of both NO and IL-6 were also found to inversely correlate with impaired lung function (%FEV1 predicted). In addition, there was a strong positive correlation between levels of IL-6 and NO found in the plasma of patients and those spontaneously produced by their peripheral blood mononuclear cells (PBMCs), identifying these cells as a major source of these key inflammatory mediators in COPD. GTS-21, an agonist for the alpha 7 nicotinic receptors (α7nAChR), was found to exert immune-modulatory actions in PBMCs of COPD patients by suppressing the production of IL-6 and NO. This study provides the first evidence supporting the therapeutic potential of α7nAChR agonists in COPD due to their ability to suppress the production of key inflammatory markers associated with disease severity.

Shared mechanisms of multimorbidity in COPD, atherosclerosis and type-2 diabetes: the neutrophil as a potential inflammatory target

Multimorbidity is increasingly common and current healthcare strategies are not always aligned to treat this complex burden of disease. COPD, type-2 diabetes mellitus (T2D) and cardiovascular disease, especially atherosclerosis, occur more frequently together than expected, even when risk factors such as smoking, obesity, inactivity and poverty are considered. This supports the possibility of unifying mechanisms that contribute to the pathogenesis or progression of each condition.Neutrophilic inflammation is causally associated with COPD, and increasingly recognised in the pathogenesis of atherosclerosis and T2D, potentially forming an aetiological link between conditions. This link might reflect an overspill of inflammation from one affected organ into the systemic circulation, exposing all organs to an increased milieu of proinflammatory cytokines. Additionally, increasing evidence supports the involvement of other processes in chronic disease pathogenesis, such as cellular senescence or changes in cellular phenotypes.This review explores the current scientific evidence for inflammation, cellular ageing and cellular processes, such as reactive oxygen species production and phenotypic changes in the pathogenesis of COPD, T2D and atherosclerosis; highlighting common mechanisms shared across these diseases. We identify emerging therapeutic approaches that target these areas, but also where more work is still required to improve our understanding of the underlying cellular biology in a multimorbid disease setting.

Effects of conjugated linoleic acid supplementation on serum levels of interleukin-6 and sirtuin 1 in COPD patients

OBJECTIVE

Chronic obstructive pulmonary disease (COPD) is characterized by systemic inflammation and accelerated inflammaging of the lungs. Some studies showed that conjugated linoleic acid (CLA) has anti-inflammatory effects. The aim of the present study was to evaluate the effect of CLA supplementation on serum levels of interleukin (IL)-6 and sirtuin1 (SIRT1) in patients with COPD.

MATERIALS AND METHODS

82 patients with stable COPD were enrolled in a double blind clinical trial. Subjects were randomly assigned to two groups: placebo (n=42) and 3.2 g CLA daily supplementation (n=40). Forced expiratory volume in one second (FEV1%), BODE index, and serum levels of IL-6, and SIRT1 were measured at the baseline and six weeks after the intervention. In addition, the study parameters in the two groups were compared based on the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria.

RESULTS

After supplementation with CLA, serum levels of IL-6 and BODE index significantly decreased (p<0.05 and p<0.001, respectively). In addition, serum levels of SIRT1 (p<0.01) and FEV1 (p<0.001) significantly increased in the supplementation group. Based on GOLD criteria, the increase in SIRT1 and the decrease in IL-6 serum levels were found to be statistically significant in stages III and IV in the supplementation group (p<0.05 and p<0.01, respectively).

CONCLUSION

Supplementation with CLA can modify the inflammatory markers and improve the health status of COPD patients. The results suggest that CLA supplementation in COPD patients can be useful in the management of the disease.

Interleukin-6 serum level and -597 A/G gene polymorphism in moderate and severe chronic obstructive pulmonary disease

Inflammation is a major pathogenic pathway in pulmonary chronic obstructive disease (COPD). Interleukin-6 (IL-6) mediates the local and systemic immune response. The aim consisted in investigating the relationship between IL-6 serum levels and IL-6 -597A/G gene polymorphism (rs1800797) with COPD. Serum levels of IL-6 were determined using an enzyme-linked immune-sorbent assay, in 120 participants (60 COPD patients and 60 healthy subjects), from Transylvanian region. The IL-6 -597A/G gene polymorphism was investigated by high molecular weight genomic DNA extracted from the peripheral blood leukocytes, and subsequently analyzed by the Polymerase Chain Reaction Restriction Fragment Length Polymorphism (PCR-RFLP) technique. Smoking history, the severity of the disease, expressed by the GOLD stages, and arterial blood partial pressure of oxygen (PaO2) levels were also investigated. COPD patients had significantly elevated blood levels of IL-6 when compared to the control group ( p < 0.05). The frequencies of AA, AG, and GG genotypes were 61.6%, 26.6%, and 11.6% in the COPD cases and 70%, 23.3%, and 6.7% in healthy subjects, respectively. There were no statistically significant differences in IL-6 rs1800797 genotypes and allele frequencies between cases and controls ( χ2 = 0.54, OR = 1.29 and χ2 = 0.21, OR = 1.48, respectively). Higher serum levels of IL-6 were found in the GG genotype subgroup in COPD patients. IL 6 levels are higher in COPD patients, where positively correlate with pack-year index, but not with clinical features. Although COPD patients did not have statistically different rs1800797 allele distribution compared to healthy subjects, the GG genotype is associated with higher IL6 serum levels.

Evaluation of lung parenchyma, blood vessels, and peripheral blood lymphocytes as a potential source of acute phase reactants in patients with COPD

Background: Previous studies have shown that the arterial wall is a potential source of inflammatory markers in COPD. Here, we sought to compare the expression of acute phase reactants (APRs) in COPD patients and controls both at the local (pulmonary arteries and lung parenchyma) and systemic (peripheral blood leukocytes and plasma) compartments. Methods: Consecutive patients undergoing elective surgery for suspected primary lung cancer were eligible for the study. Patients were categorized either as COPD or control group based on the spirometry results. Pulmonary arteries and lung parenchyma sections, peripheral blood leukocytes, and plasma samples were obtained from all participants. Gene expression levels of C-reactive protein (CRP) and serum amyloid A (SAA1, SAA2, and SAA4) were evaluated in tissue samples and peripheral blood leukocytes by reverse transciption-PCR. Plasma CRP and SAA protein levels were measured by enzyme-linked immunosorbent assays. Proteins were evaluated in paraffin-embedded lung tissues by immunohistochemistry. Results: A total of 40 patients with COPD and 62 controls were enrolled. We did not find significant differences in the gene expression between COPD and control group. Both CRP and SAA were overexpressed in the lung parenchyma compared with pulmonary arteries and peripheral blood leukocytes. The expression of SAA was significantly higher in the lung parenchyma than in the pulmonary artery (2-fold higher for SAA1 and SAA4, P=0.015 and P<0.001, respectively; 8-fold higher for SAA2, P<0.001) and peripheral blood leukocytes (16-fold higher for SAA1, 439-fold higher for SAA2, and 5-fold higher for SAA4; P<0.001). No correlation between plasma levels of inflammatory markers and their expression in the lung and peripheral blood leukocytes was observed. Conclusions: The expression of SAA in lung parenchyma is higher than in pulmonary artery and peripheral blood leukocytes. Notably, no associations were noted between lung expression of APRs and their circulating plasma levels, making the leakage of inflammatory proteins from the lung to the bloodstream unlikely. Based on these results, other potential sources of systemic inflammation in COPD (eg, the liver) need further scrutiny.

Evaluation of diacetyl mediated pulmonary effects in physiologically relevant air-liquid interface models of human primary bronchial epithelial cells

Diacetyl is an artificial flavouring agent, known to cause bronchiolitis obliterans. Diacetyl-induced pulmonary effects were assessed in human primary bronchial epithelial cells (PBEC) cultured at air-liquid interface (ALI). The PBEC-ALI models were exposed to clean air (sham) and diacetyl vapour (1, 3, 10 and 30 ppm) for 30 min. At 6 and 24 h post-exposure, cell medium was sampled for assessment of cytotoxicity measurement, and CXCL8, MMP9 secretion by ELISA. Pro-inflammatory, oxidative stress, tissue injury/repair, anti-protease and beta-defensin markers were assessed using qRT-PCR. Additionally, epidermal growth factor receptor ligands (amphiregulin) and anti-protease (SLPI) were analysed at 6 h, 8 h and 24 h post exposure to 1 and 10 ppm diacetyl. No significant cytotoxicity was observed at any exposure level. MMP9 was significantly increased in both apical and basal media at 24 h. Both SLPI and amphiregulin secretion were significantly increased following exposure to 10 ppm diacetyl. Exposure of PBEC-ALI model to diacetyl vapour resulted in significantly altered transcript expression of pro-inflammatory, oxidative stress, anti-protease, tissue injury/repair markers. Changes in transcript expression of significantly altered markers were more prominent 24 h post-exposure compared to 6 h. This study warrants further mechanistic investigations to elucidate the pulmonary effects of inhaled diacetyl vapour using physiologically relevant in vitro models.

Effect of Bufei Yishen Granules Combined with Electroacupuncture in Rats with Chronic Obstructive Pulmonary Disease via the Regulation of TLR-4/NF-κB Signaling

Background

The combined therapy of Bufei Yishen granules (BY) and electroacupuncture (EA) has shown good effects clinically in treating chronic obstructive pulmonary disease (COPD). The present study aimed to observe the effects of the BY + EA combination in a COPD rat model and dissect the potential mechanisms via Toll-like receptor (TLR) 4/nuclear factor kappa B (NF-κB) signaling.

Methods

The COPD rats were treated with normal saline, aminophylline, Bufei Yishen granules, electroacupuncture, or Bufei Yishen granules combined with electroacupuncture. The pulmonary function; lung tissue histology; levels of inflammatory factors; expression levels of TLR-4, inhibitor of nuclear factor kappa B (IκB), and NF-κB; and activation of NF-κB in the lung tissues were evaluated.

Results

Pulmonary function was markedly decreased in the COPD rats, and the lung tissue histology of the COPD rats showed severe pathological changes. The pulmonary function and lung tissue morphology in the treatment groups (APL, BY, EA, and BY + EA) were improved. The increased levels of the inflammatory cytokines interleukin (IL)-1β and IL-6 indicated a chronic inflammatory state in the COPD rats. In the BY, EA, and BY + EA groups, the levels of IL-1β and IL-6 were decreased, especially in the BY + EA group. In addition, the mRNA and protein expression levels of TLR-4, IκB, and NF-κB were obviously downregulated in the BY and BY + EA groups; and the NF-κB p65 activation was significantly decreased in the BY, EA, and BY + EA groups.

Conclusions

Bufei Yishen granules and electroacupuncture have curative effects in COPD rats, and the combination therapy of Bufei Yishen granules and electroacupuncture is superior. The TLR-4/NF-κB pathway may be involved in the potential mechanisms by which Bufei Yishen granules and electroacupuncture reduce inflammation.

Protective effect of water extract of guibi-tang against pulmonary inflammation induced by cigarette smoke and lipopolysaccharide

Water extract of guibi-tang (GB), a traditional Chinese, Japanese, and Korean herbal medicine, is used to treat memory impairment, insomnia, and peptic ulcers. The aim of this study was to investigate the protective effects of GB on pulmonary inflammation induced by cigarette smoke (CS) and lipopolysaccharide (LPS). C57BL/6 mice were used to develop a pulmonary inflammation model by exposing them to CS for 1 h per day for 7 days. LPS was intranasally administered to mice under mild anesthesia on day 5. GB was administered 1 h before CS exposure at doses of 50 or 100 mg/kg for 7 days. Our results showed that GB suppressed the CS and LPS induced elevation in inflammatory cell counts in the bronchoalveolar lavage fluid (BALF), with significant reductions in protein, tumor necrosis factor (TNF)-α, and interleukin (IL)-6 levels. Histological studies revealed that GB decreased the inflammatory cell infiltration into lung tissue caused by CS- and LPS-exposure. GB also significantly decreased the CS and LPS-induced expression of inducible nitric oxide synthase (iNOS) in the lung tissue. Taken together, GB effectively attenuated airway inflammation caused by CS and LPS. These results indicate that GB is a potential therapeutic herbal formula for pulmonary inflammatory disease.

Chronic obstructive pulmonary disease and the development of atrial fibrillation

BACKGROUND

Chronic obstructive pulmonary disease (COPD) has been associated with atrial fibrillation (AF). More insight into the epidemiology and underlying mechanisms is required to optimize management.

METHODS

The Rotterdam Study is a large, population-based cohort study with long-term follow-up. Time dependent Cox proportional hazard models were constructed to study the effect of COPD on incident AF, adjusted for age, sex and pack years of cigarette smoking, and additionally stratified according to exacerbation frequency, left atrial size and baseline systemic inflammatory levels.

RESULTS

1369 of 10,943 subjects had COPD, of whom 804 developed AF. The AF incidence rate was 14 per 1000 person years in COPD and 8 per 1000 person years in subjects without COPD. The adjusted hazard ratio (HR) for COPD subjects to develop AF as compared to subjects without COPD was 1.28 (95%CI [1.04, 1.57]). COPD subjects with frequent exacerbations had a twofold increased AF risk (HR 1.99 [1.42, 2.79]) and COPD subjects with a left atrial size ≥40 mm also had an elevated AF risk (HR 1.77 [1.07, 2.94]). COPD subjects with baseline systemic inflammatory levels above the median had significantly increased AF risks (hsCRP≥1.83 mg/L: HR 1.51 [1.13, 2.03] and IL6 ≥ 1.91 ng/L: HR 2.49 [1.18, 5.28]), whereas COPD subjects below the median had in both analyses no significantly increased AF risk.

CONCLUSIONS

COPD subjects had a 28% increased AF risk, which further increased with frequent exacerbations and an enlarged left atrium. The risk was driven by COPD subjects having elevated systemic inflammatory levels.

Elevated interleukin-6 and bronchiectasis as risk factors for acute exacerbation in patients with tuberculosis-destroyed lung with airflow limitation

Background

Patients with tuberculosis-destroyed lungs (TDLs), with airflow limitation, have clinical characteristics similar to those of patients with chronic obstructive pulmonary disease (COPD). Acute exacerbation is an important factor in the management of TDL. Therefore, the aim of this study was to investigate the factors associated with acute exacerbations in patients with stable TDL with airflow limitation.

Methods

We evaluated the clinical characteristics, such as lung function, image findings, and serum laboratory findings, including C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and interleukin (IL)-6, in patients with TDL with chronic airflow limitation (n=94). We evaluated the correlation of these parameters with acute exacerbation.

Results

We found that patients with exacerbation were more likely to have bronchiectasis than those without exacerbation (patients with exacerbation, 66.7%; patients without exacerbation, 30.5%; P=0.001). CRP and IL-6 levels were significantly higher in patients with exacerbation than in those without exacerbation (P=0.001 and P<0.001, respectively). Bronchiectasis [OR, 3.248; 95% confidence interval (CI), 1.063-9.928; P=0.039] and elevated IL-6 levels (OR, 1.128; 95% CI, 1.013-1.257; P=0.028) were the most important parameters associated with acute exacerbation in patients with TDL with airflow limitation.

Conclusions

Patients with bronchiectasis and high IL-6 levels may require more intensive treatment to prevent acute exacerbation.

Mean Platelet Volume and Platelet Distribution Width in Patients With Obstructive Sleep Apnea Syndrome and Concurrent Chronic Obstructive Pulmonary Disease

Evidence suggests that there is platelet activation in obstructive sleep apnea syndrome (OSAS) and chronic obstructive pulmonary disease (COPD). Our objective is to evaluate mean platelet volume (MPV) and platelet distribution width (PDW) in patients with overlap syndrome (OS), that is, concurrent COPD with OSAS. Mean platelet volume and PDW were assessed in consecutive patients who had undergone polysomnography and pulmonary function testing. They were divided into the following groups: controls (apnea-hypopnea index [AHI] <5/hour, and forced expiratory volume in 1st second [FEV₁]/forced vital capacity [FVC] >70%), OSAS group (AHI ≥5/hour and FEV₁/FVC >70%), and OS group (AHI ≥5/hour and FEV₁/FVC <70%). A total of 485 patients (360 males and 125 females) were included. Mean platelet volume in controls was lower compared with the other groups: 10 ± 0.9 fL for controls versus 10.3 ± 1.2 fL for OSAS ( P = .006), versus 10.7 ± 1 fL for OS ( P < .001). Additionally, MPV was higher in OS group than OSAS: 10.7 ± 1 fL versus 10.3 ± 1.2 fL, respectively ( P = .002). Platelet distribution width was lower in controls compared with the other groups: 12.9 ± 2 fL for controls versus 13.6 ± 1.9 fL for OSAS ( P = .007), versus 13.8 ± 2.3 fL for OS ( P = .008), while there was no difference between OS and OSAS groups. Mean platelet volume and PDW are increased in patients with OS compared with healthy controls, with respiratory function being the major contributor in platelet activation in this series.

Acute effects of multi-walled carbon nanotubes on primary bronchial epithelial cells from COPD patients

The risks of occupational exposure during handling of multi-walled carbon nanotubes (MWCNTs) have received limited attention to date, in particular for potentially susceptible individuals with highly prevalent chronic obstructive pulmonary disease (COPD). In this in vitro study, we simulated acute inhalation of MWCNTs employing an air-liquid interface cell exposure (ALICE) system: primary human bronchial epithelial cells from COPD patients and healthy donors (controls), cultured at the air-liquid interface (ALI) were exposed to MWCNTs. To study acute health effects on the respiratory epithelium, two different concentrations (0.16; 0.34 µg/cm²) of MWCNTs were aerosolized onto cell cultures followed by analysis after 24 h. Following MWCNT exposure, epithelial integrity and differentiation remained intact. Electron microscopy analyses identified MWCNTs both extra- and intracellular within vesicles of mucus producing cells. In both COPD and healthy control cultures, MWCNTs neither caused increased release of lactate dehydrogenase (LDH), nor alterations in inflammatory responses, as measured by RNA expression and protein secretion of the cytokines IL-6, IL-8, CXCL10, IL-1β and TGF-β and oxidative stress markers HMOX-1 and SOD-2. No short-term alteration of epithelial cell function, as determined by ciliary beating frequency (CBF), occurred in any of the conditions tested. In conclusion, the present study provided a reliable and realistic in vitro acute-exposure model of the respiratory tract, responsive to positive controls such as Dörentruper Quartz (DQ12) and asbestos. Acute exposure to MWCNTs did not affect epithelial integrity, nor induce increased cell death, apoptosis or inflammatory changes.

Instillation of particulate matter 2.5 induced acute lung injury and attenuated the injury recovery in ACE2 knockout mice

Inhaled particulate matter 2.5 (PM_2.5) can cause lung injury by inducing serious inflammation in lung tissue. Renin-angiotensin system (RAS) is involved in the pathogenesis of inflammatory lung diseases and regulates inflammatory response. Angiotensin-converting enzyme II (ACE2), which is produced through the angiotensin-converting enzyme (ACE)/angiotensin II (Ang II) axis, protects against lung disease. However, few studies have focused on the relationships between PM_2.5 and ACE2. Therefore, we aimed to explore the role of ACE2 in PM_2.5-induced acute lung injury (ALI). An animal model of PM_2.5-induced ALI was established with wild type (C57BL/6, WT) and ACE2 gene knockout (ACE2 KO) mice. The mice were exposed to PM_2.5 through intratracheal instillation once a day for 3 days (6.25 mg/kg/day) and then sacrificed at 2 days and 5 days after PM_2.5 instillation. The results show that resting respiratory rate (RRR), levels of inflammatory cytokines, ACE and MMPs in the lungs of WT and ACE2 KO mice were significantly increased at 2 days postinstillation. At 5 days postinstillation, the PM_2.5-induced ALI significantly recovered in the WT mice, but only partially recovered in the ACE2 KO mice. The results hint that PM_2.5 could induce severe ALI through pulmonary inflammation, and the repair after acute PM_2.5 postinstillation could be attenuated in the absence of ACE2. Additionally, our results show that PM_2.5-induced ALI is associated with signaling p-ERK1/2 and p-STAT3 pathways and ACE2 knockdown could increase pulmonary p-STAT3 and p-ERK1/2 levels in the PM_2.5-induced ALI.

Severity of COPD and its relationship with IL-10

BACKGROUND

The present study was designed to compare inflammatory and metabolic responses according to severity of airflow among patients with COPD and to verify the relationship between pulmonary function, body composition, metabolic and inflammatory profile.

METHODS

Fifty-one patients with mild to very severe COPD were recruited and divided according lung function in Mild-moderate (GOLD 1-2) n= 21; Severe (GOLD 3) n=25 and Very severe (GOLD 4) n=5. Patients were submitted to assessments of lung function (spirometry), functional exercise capacity (6-min walk test), body composition (Octopolar bioelectrical impedance), metabolic profile (glucose, triglycerides, total cholesterol, HDL-cholesterol and albumin (colorimetric assay)) and inflammatory profile (cytokines: IL-6, IL-10, TNF-α and IL-15 (ELISA)).

RESULTS

We found that patients in GOLD 3 group had lower levels of IL-10, triglycerides, visceral fat area, and higher IL-6 and IL-6/IL-10 ratio when compared to GOLD 1-2 patients. Additionally, GOLD 1-2 group presented negative correlation between TNF-α and HDL cholesterol (p= .01) and positive correlation between IL-15 and FEV₁/FVC (p=.01), while GOLD 3 group showed positive correlation between IL-6 and IL-10 (p< .01), IL-6 and total cholesterol (p<.01) and negative correlation between IL-10 and HDL-cholesterol (p=.01).

CONCLUSION

Our findings suggest that patients with severe COPD can exhibit compromised "inflammatory status", characterized by higher IL6, IL-6/IL-10 ratio and lower IL-10 concentration. Furthermore, IL-10 seems to be an interesting cytokine to be investigated in this kind of patients.

The value of blood cytokines and chemokines in assessing COPD

BACKGROUND

Blood biomarkers are increasingly used to stratify high risk chronic obstructive pulmonary disease (COPD) patients; however, there are fewer studies that have investigated multiple biomarkers and replicated in multiple large well-characterized cohorts of susceptible current and former smokers.

METHODS

We used two MSD multiplex panels to measure 9 cytokines and chemokines in 2123 subjects from COPDGene and 1117 subjects from SPIROMICS. These biomarkers included: interleukin (IL)-2, IL-6, IL-8, IL-10, tumor necrosis factor (TNF)-α, interferon (IFN)-γ, eotaxin/CCL-11, eotaxin-3/CCL-26, and thymus and activation-regulated chemokine (TARC)/CCL-17. Regression models adjusted for clinical covariates were used to determine which biomarkers were associated with the following COPD phenotypes: airflow obstruction (forced expiratory flow at 1 s (FEV1%) and FEV1/forced vital capacity (FEV1/FVC), chronic bronchitis, COPD exacerbations, and emphysema. Biomarker-genotype associations were assessed by genome-wide association of single nucleotide polymorphisms (SNPs).

RESULTS

Eotaxin and IL-6 were strongly associated with airflow obstruction and accounted for 3-5% of the measurement variance on top of clinical variables. IL-6 was associated with progressive airflow obstruction over 5 years and both IL-6 and IL-8 were associated with progressive emphysema over 5 years. None of the biomarkers were consistently associated with chronic bronchitis or COPD exacerbations. We identified one novel SNP (rs9302690 SNP) that was associated with CCL17 plasma measurements.

CONCLUSION

When assessing smoking related pulmonary disease, biomarkers of inflammation such as IL-2, IL-6, IL-8, and eotaxin may add additional modest predictive value on top of clinical variables alone.

TRIAL REGISTRATION

COPDGene (ClinicalTrials.gov Identifier: NCT02445183 ). Subpopulations and Intermediate Outcomes Measures in COPD Study (SPIROMICS) ( ClinicalTrials.gov Identifier: NCT 01969344 ).

The Dose-Response Association between Nitrogen Dioxide Exposure and Serum Interleukin-6 Concentrations

Systemic inflammation is an integral part of chronic obstructive pulmonary disease (COPD), and air pollution is associated with cardiorespiratory mortality, yet the interrelationships are not fully defined. We examined associations between nitrogen dioxide (NO₂) exposure (as a marker of traffic-related air pollution) and pro-inflammatory cytokines, and investigated effect modification and mediation by post-bronchodilator airflow obstruction (post-BD-AO) and cardiovascular risk. Data from middle-aged participants in the Tasmanian Longitudinal Health Study (TAHS, n = 1389) were analyzed by multivariable logistic regression, using serum interleukin (IL)-6, IL-8 and tumor necrosis factor-α (TNF-α) as the outcome. Mean annual NO₂ exposure was estimated at residential addresses using a validated satellite-based land-use regression model. Post-BD-AO was defined by post-BD forced expiratory ratio (FEV₁/FVC) < lower limit of normal, and cardiovascular risk by a history of either cerebrovascular or ischaemic heart disease. We found a positive association with increasing serum IL-6 concentration (geometric mean 1.20 (95% CI: 1.1 to 1.3, p = 0.001) per quartile increase in NO₂). This was predominantly a direct relationship, with little evidence for either effect modification or mediation via post-BD-AO, or for the small subgroup who reported cardiovascular events. However, there was some evidence consistent with serum IL-6 being on the causal pathway between NO₂ and cardiovascular risk. These findings raise the possibility that the interplay between air pollution and systemic inflammation may differ between post-BD airflow obstruction and cardiovascular diseases.

Neutrophil-mediated IL-6 receptor trans-signaling and the risk of chronic obstructive pulmonary disease and asthma

The Asp358Ala variant in the interleukin-6 receptor (IL-6R) gene has been implicated in asthma, autoimmune and cardiovascular disorders, but its role in other respiratory conditions such as chronic obstructive pulmonary disease (COPD) has not been investigated. The aims of this study were to evaluate whether there is an association between Asp358Ala and COPD or asthma risk, and to explore the role of the Asp358Ala variant in sIL-6R shedding from neutrophils and its pro-inflammatory effects in the lung. We undertook logistic regression using data from the UK Biobank and the ECLIPSE COPD cohort. Results were meta-analyzed with summary data from a further three COPD cohorts (7,519 total cases and 35,653 total controls), showing no association between Asp358Ala and COPD (OR = 1.02 [95% CI: 0.96, 1.07]). Data from the UK Biobank showed a positive association between the Asp358Ala variant and atopic asthma (OR = 1.07 [1.01, 1.13]). In a series of in vitro studies using blood samples from 37 participants, we found that shedding of sIL-6R from neutrophils was greater in carriers of the Asp358Ala minor allele than in non-carriers. Human pulmonary artery endothelial cells cultured with serum from homozygous carriers showed an increase in MCP-1 release in carriers of the minor allele, with the difference eliminated upon addition of tocilizumab. In conclusion, there is evidence that neutrophils may be an important source of sIL-6R in the lungs, and the Asp358Ala variant may have pro-inflammatory effects in lung cells. However, we were unable to identify evidence for an association between Asp358Ala and COPD.

The Correlation of Serum Brain Natriuretic Peptide and Interleukin-6 with Quality of Life Using the Chronic Obstructive Pulmonary Disease Assessment Test

OBJECTIVE

The aim of this study was to determine the levels of serum pro-brain natriuretic peptide (pro-BNP) and interleukin (IL)-6 in patients with stable chronic obstructive pulmonary disease (COPD) and to correlate these markers with health-related quality of life using the COPD assessment test (CAT).

MATERIALS AND METHODS

Serum pro-BNP and IL-6 levels were measured in 82 patients with stable COPD. Serum pro-BNP and serum IL-6 levels, pulmonary function, and oxygen saturation (SpO2) were measured according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage and CAT score. Also, the associations of both pro-BNP and IL-6 with the clinical parameters of patients were tested.

RESULTS

The serum levels of IL-6 (7.57 [5-11.16] pg/mL) and pro-BNP (120.55 [92.89-144.20] pg/mL) were higher with enhancing disease severity based on the GOLD classification (p = 0.034 and 0.068, respectively). Also, serum levels of pro-BNP (120.55 [89.50-147.90] pg/mL) and IL-6 (6.68 [4.40-11.97] pg/mL) were increased in patients with high CAT scores (p = 0.004 and 0.017, respectively). There was a significant positive correlation between plasma pro-BNP and IL-6 levels (r = 0.332, p = 0.002).

CONCLUSION

The results demonstrated that with increased severity of obstruction based on the GOLD criteria both IL-6 and pro-BNP were elevated. This increase in inflammatory markers was associated with a reduced quality of life and the severity of hypoxia. These findings indicated that lowering IL-6 and pro-BNP could be useful in the management of COPD patients.