Solid Fuel Use and Incident COPD in Chinese Adults: Findings from the China Kadoorie Biobank

BACKGROUND

Solid fuels are widely used in China. Household air pollution from the burning of solid fuels may increase the risk of chronic obstructive pulmonary disease (COPD), but prospective evidence is limited.

OBJECTIVES

We examined the association of solid fuel use for cooking and heating with the risk of COPD in a prospective cohort study.

METHODS

Participants were from the China Kadoorie Biobank. Current and previous fuels used for household cooking and heating were self-reported at baseline in 2004–2008. In the present study, "solid fuels" refers to coal and wood, whereas "cleaner fuels" refers to energy sources that presumably produce lower levels of indoor pollution, including electricity, gas, and central heating. A total of 475,827 adults 30–79 y of age without prevalent COPD were followed through the end of 2015. We used adjusted Cox regression models to estimate hazard ratios for COPD.

RESULTS

Over 9.1 y of follow-up, 9,835 incident COPD cases were reported. Compared with the use of cleaner fuels for cooking, using coal and wood for cooking was positively associated with COPD, with fully adjusted HRs of 1.06 (95% CI: 0.98, 1.15) and 1.14 (95% CI: 1.06, 1.23), respectively. Adjusted HRs for heating with coal and wood were 1.16 (95% CI: 1.04, 1.29) and 1.21 (95% CI: 1.09, 1.35), respectively. The positive association between cooking with solid fuel and COPD appeared to be limited to women and never- (vs. ever-) smokers. COPD risk increased with a higher number of years of solid fuel use for heating and wood use for cooking.

CONCLUSIONS

The use of solid fuel for cooking and heating was associated with the increased risk of COPD in this prospective cohort study. Studies with more accurate exposure assessment are needed to confirm the association. https://doi.org/10.1289/EHP2856.

Impact of prior and concurrent medication on exacerbation risk with long-acting bronchodilators in chronic obstructive pulmonary disease: a post hoc analysis

BACKGROUND

Symptomatic patients with chronic obstructive pulmonary disease (COPD) and low exacerbation risk still have disease instability, which can be improved with better bronchodilation. We evaluated two long-acting bronchodilators individually and in combination on reducing exacerbation risk and the potential impact of concurrent medication in these patients.

METHODS

Integrated post hoc intent-to-treat (ITT) analysis of data from two large 24-week, randomized placebo (PBO)-controlled trials (NCT01313637, NCT01313650). Symptomatic patients with moderate-to-very-severe COPD with/without an exacerbation history were randomized (2:3:3:3) to once-daily: PBO, umeclidinium/vilanterol (UMEC/VI 62.5/25 μg [NCT01313650] or 125/25 μg [NCT01313637]), UMEC (62.5 [NCT01313650] or 125 μg [NCT01313637]) or VI (25 μg) via the ELLIPTA inhaler. Medication subgroups were segmented by treatment status at screening: a) maintenance-naïve or on maintenance medications, b) inhaled corticosteroid [ICS]-free or ICS-treated, c) low or high albuterol use based on median run-in use (< 3.6 or ≥ 3.6 puffs/day). Time to first moderate/severe exacerbation (Cox proportional hazard model) and change from baseline in trough forced expiratory volume in 1 s (FEV1; mixed model repeated measures) were analyzed. Safety was also assessed.

RESULTS

Of 3021 patients (ITT population; UMEC/VI: n = 816; UMEC: n = 825; VI: n = 825; PBO: n = 555), 36% had a recent exacerbation history, 33% were maintenance-naïve, 51% were ICS-free. Mean baseline albuterol use was 5.1 puffs/day. In the ITT population, UMEC/VI, UMEC, and VI reduced the risk of a first exacerbation versus PBO by 58, 44, and 39%, respectively (all p < 0.05). UMEC/VI provided significant risk reductions versus PBO in all subgroups. VI had no benefit versus PBO in maintenance-naïve, ICS-free, and low rescue use patients and was significantly less effective than UMEC/VI in these subgroups. UMEC had no significant benefit versus PBO in maintenance-naïve and ICS-free patients. All bronchodilators improved FEV1 versus PBO, and UMEC/VI significantly improved FEV1 versus both monotherapies across all populations studied (p < 0.05). All bronchodilators were similarly well tolerated.

CONCLUSIONS

Results suggest that UMEC/VI reduces exacerbation risk versus PBO more consistently across medication subgroups than UMEC or VI, particularly in patients with no/low concurrent medication use. Confirmed prospectively, these findings may support first-line use of dual bronchodilation therapy in symptomatic low-risk patients.

Endothelial Progenitor Cells as Pathogenetic and Diagnostic Factors, and Potential Targets for GLP-1 in Combination with Metabolic Syndrome and Chronic Obstructive Pulmonary Disease

In clinical practice, there are patients with a combination of metabolic syndrome (MS) and chronic obstructive pulmonary disease (COPD). The pathological mechanisms linking MS and COPD are largely unknown. It remains unclear whether the effect of MS (possible obesity) has a major impact on the progression of COPD. This complicates the development of effective approaches for the treatment of patients with a diagnosis of MS and COPD. Experiments were performed on female C57BL/6 mice. Introduction of monosodium glutamate and extract of cigarette smoke was modeled to simulate the combined pathology of lipid disorders and emphysema. Biological effects of glucagon-like peptide 1 (GLP-1) and GLP-1 on endothelial progenitor cells (EPC) in vitro and in vivo were evaluated. Histological, immunohistochemical methods, biochemical methods, cytometric analysis of markers identifying EPC were used in the study. The CD31⁺ endothelial cells in vitro evaluation was produced by Flow Cytometry and Image Processing of each well with a Cytation™ 3. GLP-1 reduces the area of emphysema and increases the number of CD31⁺ endothelial cells in the lungs of mice in conditions of dyslipidemia and damage to alveolar tissue of cigarette smoke extract. The regenerative effects of GLP-1 are caused by a decrease in inflammation, a positive effect on lipid metabolism and glucose metabolism. EPC are proposed as pathogenetic and diagnostic markers of endothelial disorders in combination of MS with COPD. Based on GLP-1, it is proposed to create a drug to stimulate the regeneration of endothelium damaged in MS and COPD.

Association of fine particulate matter on acute exacerbation of chronic obstructive pulmonary disease in Yancheng, China

BACKGROUND

Epidemiological evidence on the association between short-term exposure to fine particulate matter (PM_2.5) air pollution and acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is limited in China.

OBJECTIVES

To explore the associations between PM_2.5 and AECOPD in Yancheng, China from 2015 to 2017.

METHODS

In this time-series study, we used a generalized linear model with quasi-Poisson regression to investigate the association between PM_2.5 and AECOPD admitted in two major hospitals in Yancheng. We tested the robustness of the associations using two-pollutant models and examined the potential effect modification by age, gender and season via stratification analyses. Lastly, we fitted the concentration-response curves.

RESULTS

We identified a total of 4761 AECOPD inpatients during the study period. The average daily-mean PM_2.5 concentration was 45.2 μg/m³. Each 10 μg/m³ increase in PM_2.5 concentration on the concurrent day of the onset of AECOPD was associated with a 1.05% (95% confidence interval: 0.14%, 1.96%) increase in AECOPD. The association was robust to the adjustment of ozone, but not to sulfur dioxide, nitrogen dioxide, and carbon monoxide. The association was larger in females, elderly patients, and was restricted within the cold season, but all between-group differences were insignificant. The concentration-response relationship curves were generally linear but flatted at concentrations over 40 μg/m³.

CONCLUSIONS

This study demonstrated a higher risk of AECOPD associated with present-day PM_2.5 exposure in a Chinese city. We further provided important information on lag patterns, susceptible subgroups, sensitive seasons, as well as the characteristics of the concentration-response relationship curves.

Effect of Daiqin phlegm-expelling pill on development of inflammation in rats with chronic obstructive pulmonary disease induced by lipopolysaccharide and smoke

OBJECTIVE

To investigate the effect of Daiqin phlegm-expelling pill, prepared with Traditional Chinese Medicine (TCM), on the development of inflammation in Sprague-Dawley (SD) rats with chronic obstructive pulmonary disease (COPD) induced by lipopolysaccharide (LPS) and smoke, and to identity the possible underlying mechanism.

METHODS

Sixty male rats were divided into 6 groups (healthy control group, untreated group, Daiqin phlegm-expelling pill low, middle and high dose, and ambroxol hydrochloride tablet group). COPD was established in SD rats by sootiness and tracheal instillation with LPS. The rats were treated with Daiqin phlegm-expelling pill at the indicated doses for 28 d, the inflammatory cells in bronchoalveolar lavage fluid (BALF), the concentration of tumor necrosis factor-α (TNF-α), interleukin (IL)-8 and IL-6 in blood and the inflammation in lung were evaluated.

RESULTS

The number of inflammatory cells in the BALF and TNF-α, IL-8 and IL-6 level in plasma were significantly reduced in rats with COPD when treated with Daiqin phlegm-expelling pill or ambroxol hydrochloride tablet, compared with those without any treatment. The Daiqin phlegm-expelling pill treated rats with COPD had a attenuated inflammation in lung tissue, compared with the untreated group.

CONCLUSION

Daiqin phlegm-expelling pill can significantly restrain the airway inflammation in rats with LPS-smoke induced COPD.

Spatial patterns and effects of air pollution and meteorological factors on hospitalization for chronic lung diseases in Beijing, China

Chronic obstructive pulmonary disease (COPD), lung cancer (LC) and tuberculosis (TB) are common chronic lung diseases that generate a large disease burden and significant health care resource use in China. The aim of this study was to quantify spatial patterns and effects of air pollution and meteorological factors on hospitalization of COPD, LC and TB in Beijing. Daily counts of hospitalization for 2010 were obtained from the Beijing Urban Employees Basic Medical Insurance (UEBMI) system. Bayesian hierarchical Poisson regression models were applied to identify spatial patterns of hospitalization for COPD, LC and TB at the district level and explore associations with inhalable particulate matter (aerodynamic diameter <10 μm, PM₁₀), sulfur dioxide (SO₂), nitrogen dioxide (NO₂), mean temperature and relative humidity. There were 18,882, 14,295 and 2,940 counts of hospitalizations for COPD, LC and TB respectively, in Beijing in 2010. Clusters of high relative risk were in different locations for the three diseases. The effect of relative humidity on COPD hospitalization was most significant with a relative risk (RR) of 1.070 (95%CI: 1.054, 1.086) per one percent increase. For lung cancer hospitalization, exposure to ambient SO₂ was associated with a RR of 1.034 (95%CI: 1.011, 1.058) per μg m^-3 increase. For tuberculosis, the effect of mean temperature was significant with a RR of 1.107 (95%CI: 1.038, 1.180) per °C increase. Risk factors and spatial patterns were different for hospitalization of non-infectious and infectious chronic lung disease in Beijing. Even over a short time period (one year), associations were apparent with air pollution and meteorological factors.

Memantine ameliorates pulmonary inflammation in a mice model of COPD induced by cigarette smoke combined with LPS

An enhanced chronic inflammatory response in the airways has been regarded as a critical characteristic of chronic obstructive pulmonary disease (COPD). Memantine, an N-methyl-d-aspartate (NMDA) receptors antagonist, has been reported to alleviate lung inflammation. In this study, we investigated the effect and mechanism of memantine on the COPD model induced by cigarette smoke (CS) combined with LPS. Mice and RAW264.7 cells were treated with LPS in the presence or absence of CS. We performed H&E staining to analysis the lung histopathological characteristics. Cytokines (IL-6, TNF-α, and IFN-γ) levels in bronchoalveolar lavage fluid (BALF), lung tissue homogenates and RAW264.7 cell culture medium were determined. Glutamate levels in plasma and culture medium of RAW264.7 were determined. The intracellular Ca2+ flux in RAW264.7 cells was measured by fluo-3 AM staining. The protein levels of NR-1, xCT, ERK1/2, and AKT signaling in the lung tissue and cells were investigated. The result showed that CS and LPS stimulation caused inflammation response, a significant increase in the release of cytokines, including TNF-α, IL-6, and IFN-γ, the elevated release of glutamate and protein levels of NR-1 and xCT, increased Ca2+ influx, and the activation of the ERK1/2 pathway in vitro and in vivo. The above effects of CS and LPS stimulation could be significantly attenuated by memantine treatment. In conclusion, memantine can effectively ameliorate pulmonary inflammation in CS + LPS-induced COPD in mice via reducing NR-1 and xCT expression, glutamate release, Ca2+ influx, and the phosphorylation of Erk1/2. We provided a possible mechanism by which memantine ameliorates COPD in mice.

Role of reciprocal interaction between autophagy and endoplasmic reticulum stress in apoptosis of human bronchial epithelial cells induced by cigarette smoke extract

Endoplasmic reticulum stress (ERS)-induced apoptosis of airway epithelial cells plays an important role in the pathogenesis of chronic obstructive pulmonary disease (COPD). Furthermore, autophagy is closely related to ERS under apoptosis. Here, this study aimed to investigate the role of the reciprocal interaction between autophagy and ERS in the cigarette smoke extract (CSE)-induced apoptosis of human bronchial epithelial (HBE) cells. Cell apoptosis was detected by flow cytometry analysis. Protein expression was examined by Western blot. The mRNA expression was detected using real-time quantitative reverse transcription PCR (qRT-PCR). The results showed that CSE treatment induced apoptosis, autophagy, and expression of ERS-related proteins in HBE cells. Furthermore, autophagy inhibition by 3-MA significantly decreased protein expression of GRP78, p-PERK, and p-eIF2α and increased CHOP, ATF4, and caspase-4, whereas ERS inhibition by 4-PBA led to autophagy suppression. Moreover, the CSE-induced autophagy was diminished by knockdown of GRP78, PERK, or eIF2α but enhanced by knockdown of ATF4 or CHOP; however, the CSE-induced HBE apoptosis was enhanced by knockdown of GRP78, PERK, or eIF2α but was attenuated by knockdown of ATF4 or CHOP. Additionally, both sodium hydrosulfide (NaHS) and melatonin attenuated the CSE-induced apoptosis, enhanced the CSE-induced autophagy, increased GRP78, p-PERK, and p-eIF2α, and decreased CHOP, ATF4, and caspase-4, via SIRT1/ORP150 pathway. Collectively, this study provided evidence about the role of the reciprocal interaction between autophagy and ERS in CSE-induced apoptosis of HBE cells. © 2018 IUBMB Life, 71(1):66-80, 2019.

The Aryl Hydrocarbon Receptor and the Maintenance of Lung Health

Much of what is known about the Aryl Hydrocarbon Receptor (AhR) centers on its ability to mediate the deleterious effects of the environmental toxicant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD; dioxin). However, the AhR is both ubiquitously-expressed and evolutionarily-conserved, suggesting that it evolved for purposes beyond strictly mediating responses to man-made environmental toxicants. There is growing evidence that the AhR is required for the maintenance of health, as it is implicated in physiological processes such as xenobiotic metabolism, organ development and immunity. Dysregulation of AhR expression and activity is also associated with a variety of disease states, particularly those at barrier organs such as the skin, gut and lungs. The lungs are particularly vulnerable to inhaled toxicants such as cigarette smoke. However, the role of the AhR in diseases such as chronic obstructive pulmonary disease (COPD)-a respiratory illness caused predominately by cigarette smoking-and lung cancer remains largely unexplored. This review will discuss the growing body of literature that provides evidence that the AhR protects the lungs against the damaging effects of cigarette smoke.

Evaluating Mode of Action of Acrolein Toxicity in an In Vitro Human Airway Tissue Model

Acrolein is a reactive unsaturated aldehyde and is found at high concentrations in both mainstream and side-stream tobacco smoke. Exposure to acrolein via cigarette smoking has been associated with acute lung injury, chronic obstructive pulmonary diseases (COPDs), and asthma. In this study, we developed an in vitro treatment strategy that resembles the inhalation exposure to acrolein experienced by smokers and systematically examined the adverse respiratory effects induced by the noncytotoxic doses of acrolein in a human airway epithelial tissue model. A single 10-min exposure to buffered saline containing acrolein significantly induced oxidative stress and inflammatory responses, with changes in protein oxidation and GSH depletion occurring immediately after the treatment whereas responses in inflammation requiring a manifestation time of at least 24 h. Repeated exposure to acrolein for 10 consecutive days resulted in structural and functional changes that recapitulate the pathological lesions of COPD, including alterations in the beating frequency and structures of ciliated cells, inhibition of mucin expression and secretion apparatus, and development of squamous differentiation. Although some of the early responses caused by acrolein exposure were reversible after a 10-day recovery, perturbations in the functions and structures of the air-liquid-interface (ALI) cultures, such as mucin production, cilia structures, and morphological changes, failed to fully recover over the observation period. Taken together, these findings are consistent with its mode of action that oxidative stress and inflammation have fundamental roles in acrolein-induced tissue remodeling. Furthermore, these data demonstrate the usefulness of analytical methods and testing strategy for recapitulating the key events in acrolein toxicity using an in vitro model.

Estimation of PM2.5 mortality burden in China with new exposure estimation and local concentration-response function

The estimation of PM_2.5-related mortality is becoming increasingly important. The accuracy of results is largely dependent on the selection of methods for PM_2.5 exposure assessment and Concentration-Response (C-R) function. In this study, PM_2.5 observed data from the China National Environmental Monitoring Center, satellite-derived estimation, widely collected geographic and socioeconomic information variables were applied to develop a national satellite-based Land Use Regression model and evaluate PM_2.5 exposure concentrations within 2013-2015 with the resolution of 1 km × 1 km. Population weighted concentration declined from 72.52 μg/m³ in 2013 to 57.18 μg/m³ in 2015. C-R function is another important section of health effect assessment, but most previous studies used the Integrated Exposure Regression (IER) function which may currently underestimate the excess relative risk of exceeding the exposure range in China. A new Shape Constrained Health Impact Function (SCHIF) method, which was developed from a national cohort of 189,793 Chinese men, was adopted to estimate the PM_2.5-related premature deaths in China. Results showed that 2.19 million (2013), 1.94 million (2014), 1.65 million (2015) premature deaths were attributed to PM_2.5 long-term exposure, different from previous understanding around 1.1-1.7 million. The top three provinces of the highest premature deaths were Henan, Shandong, Sichuan, while the least ones were Tibet, Hainan, Qinghai. The proportions of premature deaths caused by specific diseases were 53.2% for stroke, 20.5% for ischemic heart disease, 16.8% for chronic obstructive pulmonary disease and 9.5% for lung cancer. IER function was also used to calculate PM_2.5-related premature deaths with the same exposed level used in SCHIF method, and the comparison of results indicated that IER had made a much lower estimation with less annual amounts around 0.15-0.5 million premature deaths within 2013-2015.

The modification of indoor PM2.5 exposure to chronic obstructive pulmonary disease in Chinese elderly people: A meet-in-metabolite analysis

BACKGROUND

Exposure to airborne fine particulate matter (PM_2.5) has been associated with a variety of adverse health outcomes including chronic obstructive pulmonary disease (COPD). However, the linkages between PM_2.5 exposure, PM_2.5-related biomarkers, COPD-related biomarkers and COPD remain poorly elucidated.

OBJECTIVES

To investigate the linkages between PM_2.5 exposure and COPD outcome by using the meet-in-middle strategy based on urinary metabolic biomarkers.

METHODS

A cross-sectional study was designed to illustrate the mentioned quadripartite linkages. Indoor PM_2.5 and its element components were assessed in 41 Chinese elderly participants including COPD patients and their healthy spouses. Metabolic biomarkers involved in PM_2.5 exposure and COPD were identified by using urinary metabolomics. The associations between PM_2.5- and COPD-related biomarkers were investigated by statistics and metabolic pathway analysis.

RESULTS

Seven metabolites were screened and identified with significant correlations to PM_2.5 exposure, which were majorly involved in purine and amino acid metabolism as well as glycolysis. Ten COPD-related metabolic biomarkers were identified, which suggested that amino acid metabolism, lipid and fatty acid metabolism, and glucose metabolism were disturbed in the patients. Also, PM_2.5 and its many elemental components were significantly associated with COPD-related biomarkers. We observed that the two kinds of biomarkers (PM_2.5- and COPD-related) integrated in a locally connected network and the alterations of these metabolic biomarkers can biologically link PM_2.5 exposure to COPD outcome.

CONCLUSIONS

Our study indicated the modification of PM_2.5 to COPD via both modes of action of lowering participants' antioxidation capacity and decreasing their lung energy generation; this information would be valuable for the prevention strategy of COPD.

The burden of ozone pollution on years of life lost from chronic obstructive pulmonary disease in a city of Yangtze River Delta, China

OBJECTIVE

Ambient ozone is one of the most important air pollutants with respect to its impacts on human health and its increasing concentrations globally. However, studies which explored the burden of ozone pollution on chronic obstructive pulmonary disease (COPD) and estimated the relevant economic loss were rare.

OBJECTIVE

We explored the relationships between ambient ozone exposure and years of life lost (YLL) from COPD mortality and estimated the relevant economic loss in Ningbo, in the Yangtze River Delta of China, 2011-2015.

METHODS

A time-series study was conducted to explore the effects of ozone on YLL from COPD. Seasonal stratified analyses were performed, and the effect modification of demographic factors was estimated. In addition, the related economic loss was calculated using the method of the value per statistical life year (VSLY).

RESULTS

Averaged daily mean maximum 8-h average ozone concentration was 40.90 ppb in Ningbo, China, 2011-2015. The effect of short term ambient ozone exposure on COPD YLL was more pronounced in the cool season than in the warm season, with 10 ppb increment of ozone corresponding to 7.09(95%CI: 3.41, 10.78) years increase in the cool season and 0.31 (95%CI: -2.15, 2.77) years change in the warm season. The effect was higher in the elderly than the young. Economic loss due to excess COPD YLL related to ozone exposure accounted for 7.30% of the total economic loss due to COPD YLL in Ningbo during the study period.

CONCLUSIONS

Our findings highlight that ozone exposure was related to tremendous disease burden of COPD in Ningbo, China. The effects were more pronounced in the cool season, and the elderly were more susceptible populations.

Screening Heroin Smokers Attending Community Drug Services for COPD

BACKGROUND

Heroin smoking is associated with deprivation, early onset severe emphysema, premature morbidity and mortality, and high use of health care, but individuals engage poorly with traditional health services.

METHODS

In this cross-sectional study, we screened a population of heroin smokers, prescribed opiate substitution therapy by community drug services, for airway disease. We assessed drug exposure, respiratory symptoms, health status, and COPD prevalence. Subjects completed spirometry, completed Medical Research Council (MRC) Dyspnea Scale, COPD Assessment Tool (CAT) questionnaire, recorded drug exposure, and provided feedback.

RESULTS

A total of 753 people (73% of those approached) completed screening, with 260 participants (35%) having COPD using FEV₁/FVC < 0.7 and 293 (39%) participants having COPD using the lower limit of normal. A further 112 participants (15%) had asthma-COPD overlap (ACO) with features of COPD and asthma. Compared with those with normal spirometry, participants with COPD were more breathless (MRC score 3.1 vs 1.9; P < .001) and had worse health status (CAT score 22.9 vs 13.4; P < .001), respectively. Individuals with COPD had smoked cigarettes (P < .001), heroin (P < .001), and crack (P = .03) for longer and were more likely to still be smoking heroin (P < .01). Feedback was strongly positive, with 92% of respondents happy for other health-care appointments to be colocated with drug key worker appointments.

CONCLUSIONS

Most heroin smokers had COPD or ACO, most commonly mild to moderate disease. In high-risk areas, screening this population provides an opportunity to reduce symptoms and risk. Anchoring respiratory health screening to drug center appointments delivers high completion and satisfaction and is an appropriate model for screening other hard-to-reach populations.

Lung cellular senescence is independent of aging in a mouse model of COPD/emphysema

Cigarette smoke (CS) induces lung cellular senescence that plays an important role in the pathogenesis of chronic obstructive pulmonary disease (COPD). How aging influences cellular senescence and other molecular hallmarks, and increases the risk of CS-induced damage remains unknown. We hypothesized that aging-associated changes in lungs worsen the COPD/emphysema by CS exposure. Younger and older groups of C57BL/6J mice were exposed to chronic CS for 6 months with respective age-matched air-exposed controls. CS caused a decline in lung function and affected the lung structure of both groups of mice. No alterations were observed in the induction of inflammatory mediators between the air-exposed younger and older controls, but aging increased the severity of CS-induced lung inflammation. Aging per se increased lung cellular senescence and significant changes in damage-associated molecular patterns marker S100A8. Gene transcript analysis using the nanoString nCounter showed a significant upregulation of key pro-senescence targets by CS (Mmp12, Ccl2, Cdkn2a, Tert, Wrn, and Bub1b). Aging independently influenced lung function and structure, as well as increased susceptibility to CS-induced inflammation in emphysema, but had a negligible effect on cellular senescence. Thus, aging solely does not contribute to the induction of cellular senescence by CS in a mouse model of COPD/emphysema.

The probable roles of valsartan in alleviating chronic obstructive pulmonary disease following co-exposure to cold stress and fine particulate matter

Angiotensin II (ANG II) might play an important role in the co-effects of cold stress and fine particulate matter (PM_2.5) on chronic obstructive pulmonary disease (COPD). The purpose of this study is to evaluate the roles of valsartan in alleviating COPD following co-exposure to cold stress and PM_2.5. Both the two intervention factors are carried out upon COPD rats with the intervention of valsartan. Blockade of angiotensin receptor by valsartan decreases the levels of malondialdehyde in the normal temperature and tumor necrosis factor-α under cold stress significantly. When treated with valsartan and PM_2.5 simultaneously, the expression of 8-hydroxy-2-deoxyguanosine, nuclear factor kappa B and heme oxygenase-1 decrease significantly in the group of cold stress. In conclusion, these results indicate that valsartan might relieve the co-effects of cold stress and PM_2.5 on COPD rat lung to some degree.

Tobacco smoking in Egypt: a scoping literature review of its epidemiology and control measures

BACKGROUND

According to World Health Organization (WHO) reports, the prevalence of smoking is increasing in many developing countries, including Egypt. The aim of this study is to summarize the published data in the literature about tobacco smoking in Egypt.

METHODS

A computerized literature search of PubMed and relevant Egyptian journals was conducted using the relevant keywords. The findings of retrieved studies were extracted and discussed in a narrative approach.

RESULTS

Our search retrieved 44 relevant studies. The most updated prevalence of tobacco smoking in Egypt is 22% in 2010 and is increasing. Highly significant odds ratios were reported for sibling, parent, and peer smoking as risk factors for smoking. Cardiovascular disorders, malignant tumors, and erectile dysfunction are common complications of smoking in the Egyptian population. Efforts to control tobacco smoking are available, but inadequate.

CONCLUSIONS

Tobacco smoking is a prevalent health problem in Egypt, associated with cardiovascular disorders and malignant tumors. Health education programmes should be delivered through mass media and school-based programmes to reach a large section of the Egyptian population.

MTOR Suppresses Cigarette Smoke-Induced Epithelial Cell Death and Airway Inflammation in Chronic Obstructive Pulmonary Disease

Airway epithelial cell death and inflammation are pathological features of chronic obstructive pulmonary disease (COPD). Mechanistic target of rapamycin (MTOR) is involved in inflammation and multiple cellular processes, e.g., autophagy and apoptosis, but little is known about its function in COPD pathogenesis. In this article, we illustrate how MTOR regulates cigarette smoke (CS)-induced cell death, airway inflammation, and emphysema. Expression of MTOR was significantly decreased and its suppressive signaling protein, tuberous sclerosis 2 (TSC2), was increased in the airway epithelium of human COPD and in mouse lungs with chronic CS exposure. In human bronchial epithelial cells, CS extract (CSE) activated TSC2, inhibited MTOR, and induced autophagy. The TSC2-MTOR axis orchestrated CSE-induced autophagy, apoptosis, and necroptosis in human bronchial epithelial cells; all of which cooperatively regulated CSE-induced inflammatory cytokines IL-6 and IL-8 through the NF-κB pathway. Mice with a specific knockdown of Mtor in bronchial or alveolar epithelial cells exhibited significantly augmented airway inflammation and airspace enlargement in response to CS exposure, accompanied with enhanced levels of autophagy, apoptosis, and necroptosis in the lungs. Taken together, these data demonstrate that MTOR suppresses CS-induced inflammation and emphysema-likely through modulation of autophagy, apoptosis, and necroptosis-and thus suggest that activation of MTOR may represent a novel therapeutic strategy for COPD.

The attributable risk of chronic obstructive pulmonary disease due to ambient fine particulate pollution among older adults

BACKGROUND

The linkage between ambient fine particle pollution (PM_2.5) and chronic obstructive pulmonary disease (COPD) and the attributable risk remained largely unknown. This study determined the cross-sectional association between ambient PM_2.5 and prevalence of COPD among adults ≥50 years of age.

METHODS

We surveyed 29,290 participants aged 50 years and above in this study. The annual average concentrations of PM_2.5 derived from satellite data were used as the exposure indicator. A mixed effect model was applied to determine the associations and the burden of COPD attributable to PM_2.5. RESULTS: Among the participants, 1872 (6.39%) were classified as COPD cases. Our analysis observed a threshold concentration of 30 μg/m³ in the PM_2.5-COPD association, above which we found a linear positive exposure-response association between ambient PM_2.5 and COPD. The odds ratio (OR) for each 10 μg/m³ increase in ambient PM_2.5 was 1.21(95% CI: 1.13, 1.30). Stratified analyses suggested that males, older subjects (65 years and older) and those with lower education attainment might be the vulnerable subpopulations. We further estimated that about 13.79% (95% CI: 7.82%, 21.62%) of the COPD cases could be attributable to PM_2.5 levels higher than 30 μg/m³ in the study population.

CONCLUSION

Our analysis indicates that ambient PM_2.5 exposure could increase the risk of COPD and accounts for a substantial fraction of COPD among the study population.

MicroRNA expression in serum samples of sulfur mustard veterans as a diagnostic gateway to improve care

Sulfur mustard is a vesicant chemical warfare agent, which has been used during Iraq-Iran-war. Many veterans and civilians still suffer from long-term complications of sulfur mustard exposure, especially in their lung. Although the lung lesions of these patients are similar to Chronic Obstructive Pulmonary Disease (COPD), there are some differences due to different etiology and clinical care. Less is known on the molecular mechanism of sulfur mustard patients and specific treatment options. microRNAs are master regulators of many biological pathways and proofed to be stable surrogate markers in body fluids. Based on that microRNA expression for serum samples of sulfur mustard patients were examined, to establish specific microRNA patterns as a basis for diagnostic use and insight into affected molecular pathways. Patients were categorized based on their long-term complications into three groups and microRNA serum levels were measured. The differentially regulated microRNAs and their corresponding gene targets were identified. Cell cycle arrest, ageing and TGF-beta signaling pathways showed up to be the most deregulated pathways. The candidate microRNA miR-143-3p could be validated on all individual patients. In a ROC analysis miR-143-3p turned out to be a suitable diagnostic biomarker in the mild and severe categories of patients. Further microRNAs which might own a link to the biology of the sulfur mustard patients are miR-365a-3p, miR-200a-3p, miR-663a. miR-148a-3p, which showed up only in a validation study, might be linked to the airway complications of the sulfur mustard patients. All the other candidate microRNAs do not directly link to COPD phenotype or lung complications. In summary the microRNA screening study characterizes several molecular differences in-between the clinical categories of the sulfur mustard exposure groups and established some useful microRNA biomarkers. qPCR raw data is available via the Gene Expression Omnibus https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE110797.

Short-term effects of ambient fine particulate matter pollution on hospital visits for chronic obstructive pulmonary disease in Beijing, China

BACKGROUND

Little is known about the effect of ambient fine particulate matter (PM_2.5) on chronic obstructive pulmonary disease (COPD) in China. The objective of this study was to explore the short-term effects of PM_2.5 on outpatient and inpatient visits for COPD in Beijing, China.

METHODS

A total of 3,503,313 outpatient visits and 126,982 inpatient visits for COPD between January 1, 2010, and June 30, 2012, were identified from the Beijing Medical Claim Data for Employees. A generalized additive Poisson model was applied to estimate the percentage change with 95% confidence interval (CI) in hospital visits for COPD in relation to an interquartile range (IQR) (90.8 μg/m³) increase in PM_2.5 concentrations.

RESULTS

Short-term exposure to PM_2.5 was significantly associated with increased use of COPD-related health services. There were clear exposure-response associations of PM_2.5 with COPD outpatient and inpatient visits. An IQR increase in the concurrent day PM_2.5 concentrations was significantly associated with a 2.38% (95% CI, 2.22%-2.53%) and 6.03% (95% CI, 5.19%-6.87%) increase in daily outpatient visits and inpatient visits, respectively. Elderly people were more sensitive to the adverse effects. The estimated risk was higher during the warm season compared to the cool season.

CONCLUSIONS

Short-term exposure to PM_2.5 was associated with increased risk of hospital visits for COPD. Our findings contributed to the limited evidence concerning the effects of ambient PM_2.5 on COPD morbidity in developing countries.

Toll-like receptor 2 and 4 have opposing roles in the pathogenesis of cigarette smoke-induced chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is the third leading cause of morbidity and death and imposes major socioeconomic burdens globally. It is a progressive and disabling condition that severely impairs breathing and lung function. There is a lack of effective treatments for COPD, which is a direct consequence of the poor understanding of the underlying mechanisms involved in driving the pathogenesis of the disease. Toll-like receptor (TLR)2 and TLR4 are implicated in chronic respiratory diseases, including COPD, asthma and pulmonary fibrosis. However, their roles in the pathogenesis of COPD are controversial and conflicting evidence exists. In the current study, we investigated the role of TLR2 and TLR4 using a model of cigarette smoke (CS)-induced experimental COPD that recapitulates the hallmark features of human disease. TLR2, TLR4, and associated coreceptor mRNA expression was increased in the airways in both experimental and human COPD. Compared with wild-type (WT) mice, CS-induced pulmonary inflammation was unaltered in TLR2-deficient ( Tlr2-/-) and TLR4-deficient ( Tlr4-/-) mice. CS-induced airway fibrosis, characterized by increased collagen deposition around small airways, was not altered in Tlr2-/- mice but was attenuated in Tlr4-/- mice compared with CS-exposed WT controls. However, Tlr2-/- mice had increased CS-induced emphysema-like alveolar enlargement, apoptosis, and impaired lung function, while these features were reduced in Tlr4-/- mice compared with CS-exposed WT controls. Taken together, these data highlight the complex roles of TLRs in the pathogenesis of COPD and suggest that activation of TLR2 and/or inhibition of TLR4 may be novel therapeutic strategies for the treatment of COPD.

Fine particulate matter constituents and blood pressure in patients with chronic obstructive pulmonary disease: A panel study in Shanghai, China

OBJECTIVE

The evidence is limited about the potentially different health effects of various chemical constituents of fine particulate matter (PM_2.5). We thus assessed the acute effects of various chemical constituents of PM_2.5 on blood pressure (BP).

METHODS

We performed a longitudinal panel study with six repeated visits in 28 urban residents with chronic obstructive pulmonary disease in Shanghai, China from May to July, 2014. Twelve (43%) of them took antihypertensive medications. We measured resting BP by using a mercury sphygmomanometer and monitored real-time concentrations of PM_2.5 constituents at a nearby site. Based on the linear mixed-effects model, we evaluated the effects of 10 major constituents in PM_2.5 on BP, using a single-constituent model and a constituent-residual model after accounting for the multicollinearity.

RESULTS

We obtained a total of 168 pairs of effective BP measurements during the study period. There are moderate or high correlations among various PM_2.5 constituents. An interquartile range increase of PM_2.5 (19.1μg/m³) was associated with increments of 1.90mmHg [95% confidence interval (CI): 0.66, 3.13] in systolic BP, 0.68mmHg (95%CI: -0.02, 1.37) in diastolic BP and 1.23mmHg (95%CI: 0.19, 2.29) in pulse pressure. Some constituents of PM_2.5, including organic carbon, elemental carbon, nitrate and ammonium, were robustly associated with elevated BP after controlling for total PM_2.5 mass and accounting for multi-collinearity. Two constituents (magnesium and calcium) were associated with decreased BP.

CONCLUSIONS

Organic carbon, elemental carbon, nitrate and ammonium may be mainly responsible for elevated BP from a short-term exposure to PM_2.5.

Targeting Interleukin-17 signalling in cigarette smoke-induced lung disease: Mechanistic concepts and therapeutic opportunities

It is widely accepted that compromised lung function in chronic obstructive pulmonary disease (COPD) is, at least in part, a consequence of persistent airway inflammation caused by particles and noxious gases present in cigarette smoke and indoor air pollution from burning biomass fuel. Currently, the World Health Organization estimates that 80 million people have moderate or severe COPD worldwide. While there is a global need for effective medical treatment, current therapeutic interventions have shown limited success in preventing disease pathology and progression. This is, in large part, due to the complexity and heterogeneity of COPD, and an incomplete understanding of the molecular mechanisms governing inflammatory processes in individual patients. This review discusses recent discoveries related to the pro-inflammatory cytokine interleukin (IL)-17A, and its potential role in the pathogenesis of COPD. We propose that an intervention strategy targeting IL-17 signalling offers an exciting opportunity to mitigate inflammatory processes, and prevent the progression of tissue pathologies associated with COPD.

Early-onset, Severe Chronic Obstructive Pulmonary Disease with Pulmonary Hypertension that was Likely Induced by Toluene Exposure

Early-onset pulmonary emphysema is uncommon and its pathogenesis is poorly defined. A 30-year-old man was admitted to our intensive care unit with severe respiratory failure. Besides smoking heavily since the 14 years of age, he had habitually inhaled organic solvents, such as toluene, in his adolescence. High-resolution computed tomography showed evident pulmonary emphysema throughout the lung fields. Based on the findings of right heart catheterization, he was diagnosed with an acute exacerbation of chronic obstructive pulmonary disease complicated with pulmonary hypertension. Heavy smoking from a young age and exposure to toluene were the suspected causes of the patient's severe pulmonary emphysema.