Should chronic obstructive pulmonary disease outpatients be routinely evaluated for trace elements?

We searched for serum concentrations of trace elements and correlated them to malondialdehyde (MDA), which is an indirect marker of oxidative stress, in order to clarify if routine evaluation is necessary in chronic obstructive pulmonary disease (COPD) outpatients. Serum concentrations of copper (Cu), zinc (Zn), and magnesium (Mg) were determined by atomic absorption spectrophotometry and iron (Fe) by a ILLab 1800 autoanalyzer with ILLab test kits. Serum MDA concentrations were detected in terms of TBARS (thiobarbituric acid reactive substances) spectrophotometrically. Serum Cu, Zn, Mg, Fe, and MDA concentrations in patient and control groups were all in the normal reference range. The results respectively were as follows: Cu:123±29.2 and 122.2±23.4 μg/dL; Zn: 87.8±17.8 and 96.9 ± 12.9 μg/dL; Mg: 2.3±0,5 and 2.04±0.28 mg/dL; Fe: 73.8±35.5 and 80.7±51.2 μg/dL; MDA: 1.09±0.11 and 0.95±0.06 nmol/L. MDA was not correlated to Cu, Zn, Mg, or Fe (p>0.05 for all). The serum Zn concentration of COPD group was lower than the control group (p=0.042), whereas the Mg concentration was higher (p=0.021). There was no statistical difference in other study parameters. Oxidative stress was not increased in clinically stable, regularly treated COPD patients. Although there was no deficiency in trace elements (Cu, Fe, Mg, and Zn), serum Zn was close to the lower limit of the reference value. There is no need for routine evaluation of trace elements in clinically stable, regularly treated COPD outpatients.     

Chronic obstructive pulmonary disease, asthma and protective effects of food intake: from hypothesis to evidence?

Evidence for a role of diet in asthma and chronic obstructive pulmonary disease (COPD) has been accumulating rapidly over the past decade. Associations have been reported between the intake of fruit, fish, antioxidant vitamins, fatty acids, sodium or magnesium, and indicators of asthma and COPD. Several issues need to be addressed before causality of these associations can be established. The role of diet in the development of disease and the induction time and reversibility of the effect needs further investigation. The role of smoking habits in the relation of diet and respiratory disease also needs to be elucidated. Nevertheless, based on the available evidence, dietary guidelines could be proposed for the primary and secondary prevention of asthma and COPD that are in line with existing dietary guidelines for the prevention of coronary heart disease and cancer.     

Long acting β2 agonists for stable chronic obstructive pulmonary disease with poor reversibility: a systematic review of randomised controlled trials

Background

The long acting β2-agonists, salmeterol and formoterol, have been recommended, by some, as first line treatment of stable chronic obstructive pulmonary disease (COPD). We reviewed evidence of efficacy and safety when compared with placebo or anticholinergic agents in patients with poorly reversible COPD.

Methods

After searching MEDLINE, EMBASE, HealthSTAR, BIOSIS Previews, PASCAL, ToxFile, SciSearch, the Cochrane Library, and PubMed, as well as Web sites, selected journals, reference lists, and contacting drug manufacturers, two reviewers independently screened reports of randomised controlled trials of parallel or crossover design lasting four weeks or longer and including patients with a forced expiratory volume in one second (FEV1) ≤ 75% of predicted, a ratio of FEV1 to forced vital capacity (FVC) ≤ 88% of predicted, and < 15% improvement from baseline FEV1 after a dose of a β2 agonist. We included trials comparing salmeterol or formoterol with placebo or with ipratropium bromide and reporting one of these outcomes: lung function; exercise capacity; quality of life scores; dyspnea; exacerbations; rescue inhaler use; incidence of tachycardia, hypokalemia, or dry mouth. Two reviewers assessed the quality of included reports using the Jadad scale and allocation concealment, and abstracted data.

Results

Twelve trials satisfied our inclusion criteria; eight were high quality (Jadad score >2) and four were low quality (≤ 2). The adequacy of allocation concealment was unclear in all of them. We did not perform a meta-analysis due to differences in trial design and how outcomes were reported. Two trials comparing salmeterol with ipratropium did not detect differences; one trial comparing formoterol and ipratropium described greater improvement with formoterol in morning PEFR (15.3 versus 7.1 l/min, p = 0.040). Of twelve trials comparing long acting β2 agonists with placebo, six reported no improvement in exercise capacity, eleven reported improvements in FEV1 lung function (one reported no improvement), six reported less rescue inhaler usage (one reported no difference) and five reported improved dyspnea scores (two reported no improvement). Differences in quality of life were detected in one salmeterol trial ; however, two salmeterol, and one formoterol trial reported no differences. Adverse effects of interest were not reported.

Conclusion

In terms of clinical outcomes and safety, we could not find convincing evidence that salmeterol and formoterol have demonstrated advantages to ipratropium, a less expensive drug, for patients with stable COPD and poor reversibility. Compared to placebo, we found evidence of reduced rescue inhaler usage and improved spirometric outcomes without a significant impact on quality of life or exercise capacity.     

α1,6-Fucosyltransferase (Fut8) is implicated in vulnerability to elastase-induced emphysema in mice and a possible non-invasive predictive marker for disease progression and exacerbations in chronic obstructive pulmonary disease (COPD)

Fut8 (α1,6-Fucosyltransferase) heterozygous knock-out (Fut8(+/-)) mice had an increased influx of inflammatory cells into the lungs, and this was associated with an up-regulation of matrix metalloproteinases, MMP-2 and MMP-9, after treatment with porcine pancreatic elastase (PPE), exhibiting an emphysema-prone phenotype as compared with wild type mice (Fut8(+/+)). The present data as well as our previous data on cigarette-smoke-induced emphysema [8] led us to hypothesize that reduced Fut8 levels leads to COPD with increased inflammatory response in humans and is associated with disease progression. To test this hypothesis, symptomatic current or ex-smokers with stable COPD or at risk outpatients were recruited. We investigated the association between serum Fut8 activity and disease severity, including the extent of emphysema (percentage of low-attenuation area; LAA%), airflow limitation, and the annual rate of decline in forced expiratory volume in 1 s (FEV(1)). Association with the exacerbation of COPD was also evaluated over a 3-year period. Serum Fut8 and MMP-9 activity were measured. Fut8 activity significantly increased with age among the at risk patients. In the case of COPD patients, however, the association was not clearly observed. A faster annual decline of FEV(1) was significantly associated with lower Fut8 activity. Patients with lower Fut8 activity experienced exacerbations more frequently. These data suggest that reduced Fut8 activity is associated with the progression of COPD and serum Fut8 activity is a non-invasive predictive biomarker candidate for progression and exacerbation of COPD.     

Serum macrophage inhibitory cytokine-1 as a clinical marker for non–small cell lung cancer

The aim of this study was to investigate the value of serum macrophage inhibitory factor-1 (MIC-1) level in patients with non–small cell lung cancer (NSCLC). Serum samples from 296 patients with NSCLC and 240 healthy controls were collected. The levels of serum MIC-1 were determined by ELISA. The serum MIC-1 levels in NSCLC patients were higher than that of the controls (P <.001). Univariate and multivariate Cox regression analysis showed that serum MIC-1 was an independent prognostic indicator of OS and PFS. Serum MIC-1 is a valuable biomarker for the diagnosis and prognosis of NSCLC.     

Enhanced expression of human β-defensin 2 in peripheral lungs of patients with chronic obstructive pulmonary disease

Human β-defensin 2 (hBD-2) has antimicrobial activity and may play a role in airway mucosal defense, but studies have not yet examined its expression in lung tissue of patients with chronic obstructive pulmonary disease (COPD). Here we investigated hBD-2 levels in lung tissues of COPD patients and analyzed their correlations with IL-8, IL-1β, cigarette smoking and lung function in order to see whether the protein may be involved in pathogenesis of the disease. Peripheral lung tissue specimens were obtained from 51 patients who underwent lung resection for peripheral lung cancer: healthy non-smokers (n = 8), healthy current smokers (n = 7), non-smokers with COPD (n = 11), and current smokers with COPD (n = 25). RT-PCR and immunohistochemical staining were used to detect expression levels of hBD-2, IL-8 and IL-1β. Expression of hBD-2 mRNA was significantly higher in COPD patients than in healthy controls, and significantly higher in current smokers than in non-smokers (p < 0.05). Among healthy controls, hBD-2 mRNA levels were similar between current smokers and non-smokers. Immunohistochemistry showed hBD-2 protein to be expressed mainly in epithelia of distal bronchioles and its expression pattern among our patient groups mirrored that of the mRNA. IL-8 mRNA levels were significantly higher in COPD patients than in healthy controls (p < 0.05), while IL-1β mRNA levels did not differ significantly among the groups. Levels of hBD-2 mRNA positively correlated with levels of IL-8 mRNA (r = 0.545, p = 0.002), and negatively correlated with FEV1/FVC ratios and with predicted FEV1% values (r = −0.406, p = 0.011). Our results indicate that hBD-2 expression is elevated in distal airways of COPD patients and that it may be involved in pathogenesis of the disease. Our data implicate cigarette smoking as a factor that may elevate hBD-2 levels in lung tissues of COPD patients.     

CFTR gene mutations – including three novel nucleotide substitutions – and haplotype background in patients with asthma, disseminated bronchiectasis and chronic obstructive pulmonary disease

In order to investigate the incidence of cystic fibrosis transmembrane conductance regulator (CFTR) gene mutations and unclassified variants in chronic pulmonary disease in children and adults, we studied 20 patients with asthma, 19 with disseminated bronchiectasis (DB) of unknown aetiology, and 12 patients with chronic obstructive pulmonary disease (COPD), and compared the results to 52 subjects from the general Greek population. Analysis of the whole coding region of the CFTR gene and its flanking intronic regions revealed that the proportion of CFTR mutations was 45% in asthma (P<0.05), 26.3% in DB (P>0.05), 16.7% in COPD (P>0.05), compared to 15.4% in the general population. Seventeen different molecular defects involved in disease predisposition were identified in 16 patients. Three potentially disease-causing mutations, T388 M, M1R and V11I, are novel, found so far only in three asthma patients. The hyperactive M470 allele was found more frequently in COPD patients (frequency 70.8%, P<0.01) than in the controls. The study of the TGmTnM470 V polyvariant CFTR allele revealed the presence of CFTR function-modulating haplotypes TG13/T5/M470, TG11/T5/M470, TG12/T5/V470 and TG12/T7, combined with M470 or V470, in six asthma patients, four DB patients (P<0.01), and two COPD patients (P<0.05). These results confirm the involvement of the CFTR gene in asthma, DB and possibly in COPD.     

Acquired defects in CFTR-dependent β-adrenergic sweat secretion in chronic obstructive pulmonary disease

Rationale

Smoking-induced chronic obstructive pulmonary disease (COPD) is associated with acquired systemic cystic fibrosis transmembrane conductance regulator (CFTR) dysfunction. Recently, sweat evaporimetry has been shown to efficiently measure β-adrenergic sweat rate and specifically quantify CFTR function in the secretory coil of the sweat gland.

Objectives

To evaluate the presence and severity of systemic CFTR dysfunction in smoking-related lung disease using sweat evaporimetry to determine CFTR-dependent sweat rate.

Methods

We recruited a cohort of patients consisting of healthy never smokers (N = 18), healthy smokers (12), COPD smokers (25), and COPD former smokers (12) and measured β-adrenergic sweat secretion rate with evaporative water loss, sweat chloride, and clinical data (spirometry and symptom questionnaires).

Measurements and main results

β-adrenergic sweat rate was reduced in COPD smokers (41.9 ± 3.4, P < 0.05, ± SEM) and COPD former smokers (39.0 ± 5.4, P < 0.05) compared to healthy controls (53.6 ± 3.4). Similarly, sweat chloride was significantly greater in COPD smokers (32.8 ± 3.3, P < 0.01) and COPD former smokers (37.8 ± 6.0, P < 0.01) vs. healthy controls (19.1 ± 2.5). Univariate analysis revealed a significant association between β-adrenergic sweat rate and female gender (β = 0.26), age (−0.28), FEV₁% (0.35), dyspnea (−0.3), and history of smoking (−0.27; each P < 0.05). Stepwise multivariate regression included gender (0.39) and COPD (−0.43) in the final model (R² = 0.266, P < 0.0001).

Conclusions

β-adrenergic sweat rate was significantly reduced in COPD patients, regardless of smoking status, reflecting acquired CFTR dysfunction and abnormal gland secretion in the skin that can persist despite smoking cessation. β-adrenergic sweat rate and sweat chloride are associated with COPD severity and clinical symptoms, supporting the hypothesis that CFTR decrements have a causative role in COPD pathogenesis.     

IL-1α/IL-1R1 expression in chronic obstructive pulmonary disease and mechanistic relevance to smoke-induced neutrophilia in mice

Background

Cigarette smoking is the main risk factor for the development of chronic obstructive pulmonary disease (COPD), a major cause of morbidity and mortality worldwide. Despite this, the cellular and molecular mechanisms that contribute to COPD pathogenesis are still poorly understood.

Methodology and Principal Findings

The objective of this study was to assess IL-1 α and β expression in COPD patients and to investigate their respective roles in perpetuating cigarette smoke-induced inflammation. Functional studies were pursued in smoke-exposed mice using gene-deficient animals, as well as blocking antibodies for IL-1α and β. Here, we demonstrate an underappreciated role for IL-1α expression in COPD. While a strong correlation existed between IL-1α and β levels in patients during stable disease and periods of exacerbation, neutrophilic inflammation was shown to be IL-1α-dependent, and IL-1β- and caspase-1-independent in a murine model of cigarette smoke exposure. As IL-1α was predominantly expressed by hematopoietic cells in COPD patients and in mice exposed to cigarette smoke, studies pursued in bone marrow chimeric mice demonstrated that the crosstalk between IL-1α+ hematopoietic cells and the IL-1R1+ epithelial cells regulates smoke-induced inflammation. IL-1α/IL-1R1-dependent activation of the airway epithelium also led to exacerbated inflammatory responses in H1N1 influenza virus infected smoke-exposed mice, a previously reported model of COPD exacerbation.

Conclusions and Significance

This study provides compelling evidence that IL-1α is central to the initiation of smoke-induced neutrophilic inflammation and suggests that IL-1α/IL-1R1 targeted therapies may be relevant for limiting inflammation and exacerbations in COPD.     

"GOLD or lower limit of normal definition? a comparison with expert-based diagnosis of chronic obstructive pulmonary disease in a prospective cohort-study"

Background

The Global initiative for chronic Obstructive Lung Disease (GOLD) defines COPD as a fixed post-bronchodilator ratio of forced expiratory volume in 1 second and forced vital capacity (FEV1/FVC) below 0.7. Age-dependent cut-off values below the lower fifth percentile (LLN) of this ratio derived from the general population have been proposed as an alternative. We wanted to assess the diagnostic accuracy and prognostic capability of the GOLD and LLN definition when compared to an expert-based diagnosis.

Methods

In a prospective cohort study, 405 patients aged ≥ 65 years with a general practitioner''s diagnosis of COPD were recruited and followed up for 4.5 (median; quartiles 3.9; 5.1) years. Prevalence rates of COPD according to GOLD and three LLN definitions and diagnostic performance measurements were calculated. The reference standard was the diagnosis of COPD of an expert panel that used all available diagnostic information, including spirometry and bodyplethysmography.

Results

Compared to the expert panel diagnosis, ''GOLD-COPD'' misclassified 69 (28%) patients, and the three LLNs misclassified 114 (46%), 96 (39%), and 98 (40%) patients, respectively. The GOLD classification led to more false positives, the LLNs to more false negative diagnoses. The main predictors beyond the FEV1/FVC ratio for an expert diagnosis of COPD were the FEV1 % predicted, and the residual volume/total lung capacity ratio (RV/TLC). Adding FEV1 and RV/TLC to GOLD or LLN improved the diagnostic accuracy, resulting in a significant reduction of up to 50% of the number of misdiagnoses. The expert diagnosis of COPD better predicts exacerbations, hospitalizations and mortality than GOLD or LLN.

Conclusions

GOLD criteria over-diagnose COPD, while LLN definitions under-diagnose COPD in elderly patients as compared to an expert panel diagnosis. Incorporating FEV1 and RV/TLC into the GOLD-COPD or LLN-based definition brings both definitions closer to expert panel diagnosis of COPD, and to daily clinical practice.     

Gasdermin D is an executor of pyroptosis and required for interleukin-1β secretion

Inflammasome is an intracellular signaling complex of the innate immune system. Activation of inflammasomes promotes the secretion of interleukin 1β (IL-1β) and IL-18 and triggers pyroptosis. Caspase-1 and -11 (or -4/5 in human) in the canonical and non-canonical inflammasome pathways, respectively, are crucial for inflammasome-mediated inflammatory responses. Here we report that gasdermin D (GSDMD) is another crucial component of inflammasomes. We discovered the presence of GSDMD protein in nigericin-induced NLRP3 inflammasomes by a quantitative mass spectrometry-based analysis. Gene deletion of GSDMD demonstrated that GSDMD is required for pyroptosis and for the secretion but not proteolytic maturation of IL-1β in both canonical and non-canonical inflammasome responses. It was known that GSDMD is a substrate of caspase-1 and we showed its cleavage at the predicted site during inflammasome activation and that this cleavage was required for pyroptosis and IL-1β secretion. Expression of the N-terminal proteolytic fragment of GSDMD can trigger cell death and N-terminal modification such as tagging with Flag sequence disrupted the function of GSDMD. We also found that pro-caspase-1 is capable of processing GSDMD and ASC is not essential for GSDMD to function. Further analyses of LPS plus nigericin- or Salmonella typhimurium-treated macrophage cell lines and primary cells showed that apoptosis became apparent in Gsdmd^−/− cells, indicating a suppression of apoptosis by pyroptosis. The induction of apoptosis required NLRP3 or other inflammasome receptors and ASC, and caspase-1 may partially contribute to the activation of apoptotic caspases in Gsdmd^−/− cells. These data provide new insights into the molecular mechanisms of pyroptosis and reveal an unexpected interplay between apoptosis and pyroptosis.     

Th2 cytokines and asthma — Interleukin-9 as a therapeutic target for asthma

Asthma is a complex heritable inflammatory disorder of the airways in which the development of clinical disease depends on environmental exposure. It has been well established that T helper type 2 (T_H2) lymphocytes and their cytokines have an important role in allergic asthma. Interleukin (IL)-9, a member of the T_H2 cytokine family, has recently been implicated as an essential factor in determining mucosal immunity and susceptibility to atopic asthma. In this review we examine the critical experiments and observations that support this hypothesis. We also discuss these results in comparison with the experiments supporting the involvement of other T_H2 cytokines such as IL-4, IL-5 and IL-13.     

Clinical variables predicting the risk of a hospital stay for longer than 7 days in patients with severe acute exacerbations of chronic obstructive pulmonary disease: a prospective study

Background

Chronic obstructive pulmonary disease (COPD) patients may experience an acute exacerbation (AECOPD) that requires hospitalisation. The length of hospital stay (LHS) has a great economic impact on the health-care system. Knowing the predictors of prolonged LHS could help to identify possible interventions.

Methods

We performed a prospective study to identify the clinical predictors of prolonged LHS in patients hospitalised for AECOPD. We divided the study sample by LHS into normal (≤7?days) and prolonged LHS (>?7?days) groups. Outcomes were the need for non-invasive and invasive mechanical ventilation (NIMV and IMV), intensive care unit (ICU) admission, and the 3-year mortality.

Results

We enrolled 437 patients, of which 213 and 224 had normal LHS and prolonged LHS, respectively. Patients with a prolonged LHS had more prior hospitalisations for AECOPD, a worse mMRC (modified Medical Research Council) dyspnoea score, a higher prevalence of long-term oxygen therapy and a higher rate of congestive heart disease. During the current admission, this group also tended to require NIMV, IMV and ICU admission and the mortality risks at 6?months, 1?year and 3?years were higher. In the multivariate regression analysis, an mMRC dyspnoea score?≥?2 (odds ratio-OR 2.24; 95% confidence interval-CI 1.34 to 3.74; p?=?0.002) and the presence of acute respiratory acidosis (OR 2.75; 95% CI 1.49 to 5.05; p?=?0.001) predicted a prolonged LHS at admission.

Conclusions

The presence of an mMRC ≥2 and acute respiratory acidosis at admission independently increased the risk of a prolonged LHS for AECOPD.

     

Serum bilirubin levels in familial hypercholesterolemia: a new risk marker for cardiovascular disease?

Low concentrations of bilirubin are associated with an increased risk for cardiovascular disease (CVD). Possibly, bilirubin exerts its effect through the protection of LDL from oxidation. Therefore, we examined whether low bilirubin might also be a risk marker for CVD in patients with familial hypercholesterolemia (FH) and whether statins influence serum bilirubin levels. Patients with FH were recruited from 37 lipid clinics. After a washout period of 6 weeks, all patients were started on monotherapy with simvastatin 80 mg for a period of two years. A total of 514 patients were enrolled. Bilirubin at baseline was inversely associated with the presence of CVD, also after adjustment for age, gender, presence of hypertension, and HDL cholesterol levels. Moreover, bilirubin levels were significantly raised, by 7%, from 10.0 to 10.8 μmol/L after treatment with simvastatin 80 mg. We hypothesize first that high bilirubin levels might protect patients with FH from CVD. Furthermore, bilirubin levels were significantly increased after treatment with simvastatin 80 mg, independent of changes in liver enzymes, which might confer additional protection against CVD. Whether this is also true for lower doses of simvastatin or for other statins remains to be investigated.