Respiratory long COVID in aged hamsters features impaired lung function post-exercise with bronchiolization and fibrosis

Long-term consequences of SARS-CoV-2 infection affect millions of people and strain public health systems. The underlying pathomechanisms remain unclear, necessitating further research in appropriate animal models. This study aimed to characterize the trajectory of lung regeneration over 112 days in the male hamster model by combining morphological, transcriptomic and functional readouts. We demonstrate that in the acute phase, SARS-CoV-2 Delta-infected, male, aged hamsters show a severe impairment of lung function at rest. In the chronic phase, similar impairments persisted up to 7 weeks post-infection but were only evident after exercise on a rodent treadmill. The male hamster model recapitulates chronic pulmonary fibrotic changes observed in many patients with respiratory long COVID, but lacks extra-pulmonary long-term lesions. We show that sub-pleural and interstitial pulmonary fibrosis as well as alveolar bronchiolization persist until 112 dpi. Interestingly, CK8+ alveolar differentiation intermediate (ADI) cells are becoming less prominent in the alveolar proliferation areas from 28 dpi on. Instead, CK14+ airway basal cells and SCGB1A1+ club cells, expressing cell proliferation markers, mainly populate alveolar bronchiolization areas at later time-points. We postulate that pulmonary fibrosis and SCGB1A1+ club cell-rich areas of alveolar bronchiolization represent potential risk factors for other diseases in long-COVID survivors.

Reprint of: Smoking and pulmonary health in women: A narrative review and behavioral health perspective

OBJECTIVE

Cigarette smoking prevalence has declined slower among women than men, and smoking-related pulmonary disease (PD) has risen among women. Given these trends, there is a critical need to understand and mitigate PD risk among women who smoke. The purpose of this narrative review and commentary is to highlight important evidence from the literature on smoking and PD among women.

METHODS

This review focuses broadly on examining cigarette smoking and PD among women within six topic areas: (1) demographic characteristics and prevalence of smoking, (2) smoking behavior, (3) lung cancer, (4) obstructive PD, (5) diagnostic and treatment disparities, and (6) gaps in the literature and potential directions for future research and treatment.

RESULTS

Growing evidence indicates that compared to men, women are at increased risk for developing smoking-related PD and poorer PD outcomes. Gender disparities in smoking-related PD may be largely accounted for by genetic differences and sex hormones contributing to PD pathogenesis and presentation, smoking behavior, nicotine dependence, and pathogen/carcinogen clearance. Moreover, gender disparities in smoking-related PD may be exacerbated by important social determinants (e.g., women with less formal education and those from minoritized groups may be at especially high risk for poor PD outcomes due to higher rates of smoking).

CONCLUSION

Rising rates of smoking-related PD among women risk widening diagnostic and treatment disparities. Ongoing research is needed to explore potentially complex relationships between sex, gender, and smoking-related PD processes and outcomes, and to improve smoking-cessation and PD treatment for women.

Smoking and pulmonary health in women: A narrative review and behavioral health perspective

OBJECTIVE

Cigarette smoking prevalence has declined slower among women than men, and smoking-related pulmonary disease (PD) has risen among women. Given these trends, there is a critical need to understand and mitigate PD risk among women who smoke. The purpose of this narrative review and commentary is to highlight important evidence from the literature on smoking and PD among women.

METHODS

This review focuses broadly on examining cigarette smoking and PD among women within six topic areas: (1) demographic characteristics and prevalence of smoking, (2) smoking behavior, (3) lung cancer, (4) obstructive PD, (5) diagnostic and treatment disparities, and (6) gaps in the literature and potential directions for future research and treatment.

RESULTS

Growing evidence indicates that compared to men, women are at increased risk for developing smoking-related PD and poorer PD outcomes. Gender disparities in smoking-related PD may be largely accounted for by genetic differences and sex hormones contributing to PD pathogenesis and presentation, smoking behavior, nicotine dependence, and pathogen/carcinogen clearance. Moreover, gender disparities in smoking-related PD may be exacerbated by important social determinants (e.g., women with less formal education and those from minoritized groups may be at especially high risk for poor PD outcomes due to higher rates of smoking).

CONCLUSION

Rising rates of smoking-related PD among women risk widening diagnostic and treatment disparities. Ongoing research is needed to explore potentially complex relationships between sex, gender, and smoking-related PD processes and outcomes, and to improve smoking-cessation and PD treatment for women.

Smoking Increases the Risk of Hepatocellular Carcinoma and Cardiovascular Disease in Patients with Metabolic-Associated Fatty Liver Disease

The association of smoking with hepatocellular carcinoma (HCC) or cardiovascular disease (CVD) has been reported, but the study of its relationship with metabolic-associated fatty liver disease (MAFLD) is limited. We aimed to investigate the effect of smoking on the incidence of HCC or CVD in MAFLD patients. Using the Korean nationwide health screening database, we analyzed subjects between 2001 and 2015. A total of 283,088 subjects including 110,863 MAFLD patients and 172,225 controls were analyzed. Smoking status was divided by non-smoker, ex-smoker, or current smoker. In the follow-up period, a total of 2903 (1.0%) subjects developed HCC, and the MAFLD group (1723, 1.6%) had a significantly higher incidence than the control group (1180, 0.7%). In the MAFLD group, current smokers showed significantly higher risk of HCC compared to non-smokers (adjusted HR 1.24, 95% CI 1.08-1.41), whereas the control group did not (adjusted HR 1.07, 95% CI 0.89-1.30). A total of 18,984 (6.7%) patients developed CVD, and the incidence was significantly higher in the MAFLD group (8688, 7.8%) than in the control group (10,296, 6.0%), similar to HCC. The risk of CVD in current smokers increased by 22% compared to non-smokers in the MAFLD group (adjusted HR 1.22, 95% CI 1.15-1.30) and by 21% (adjusted HR 1.21, 95% CI 1.13-1.29) in the control group. Based on sex stratification, men showed increased incidence of both HCC and CVD by smoking, whereas women had only increased risk of CVD. Smoking significantly increases the incidence of HCC and CVD in MAFLD patients; thus, it is highly recommended to quit smoking completely in the population with MAFLD.

Immunoprofiling bronchoalveolar lavage cells reveals multifaceted smoking-associated immune dysfunction

Background

Bronchoalveolar lavage (BAL) is an underutilised tool in the search for pulmonary disease biomarkers. While leukocytes with effector and suppressor function play important roles in airway immunity and tumours, it remains unclear if frequencies and phenotypes of BAL leukocytes can be useful parameters in lung cancer studies and clinical trials. We therefore explored the utility of BAL leukocytes as a source of biomarkers interrogating the impact of smoking, a major lung cancer risk determinant, on pulmonary immunity.

Methods

In this "test case" observational study, BAL samples from 119 donors undergoing lung cancer screening and biopsy procedures were evaluated by conventional and spectral flow cytometry to exemplify the comprehensive immune analyses possible with this biospecimen. Proportions of major leukocyte populations and phenotypic markers levels were found. Multivariate linear rank sum analysis considering age, sex, cancer diagnosis and smoking status was performed.

Results

Significantly increased frequencies of myeloid-derived suppressor cells and PD-L1-expressing macrophages were found in current and former smokers compared to never-smokers. While cytotoxic CD8 T-cells and conventional CD4 helper T-cell frequencies were significantly reduced in current and former smokers, expression of immune checkpoints PD-1 and LAG-3 as well as Tregs proportions were increased. Lastly, the cellularity, viability and stability of several immune readouts under cryostorage suggested BAL samples are useful for correlative end-points in clinical trials.

Conclusions

Smoking is associated with heightened markers of immune dysfunction, readily assayable in BAL, that may reflect a permissive environment for cancer development and progression in the airway.

The involvement of copper, circular RNAs, and inflammatory cytokines in chronic respiratory disease

Exposure to high concentrations of copper is associated with pulmonary inflammation and chronic respiratory disease (CRD). Epigenetic modulation of noncoding RNAs contributes to the development of several CRDs. It is unknown whether epigenetic modulation is involved in copper mediated pulmonary inflammation and CRD. We conducted a case-control study of 101 CRD cases and 161 control subjects in Shijiazhuang, China, and evaluated circRNAs and cytokine levels (IL-6 and IL-8) by qPCR and ELISA. Urinary copper concentration was determined by inductively coupled plasma mass spectrometry. Linear mixed models and generalized linear mixed models were used to assess the associations of circRNAs with CRD, urinary copper, and cytokines. We exposed the human bronchial epithelial cell line, 16HBE, to copper and assessed the functional role of a circRNA, circ_0008882, by RNA overexpression. Cellular location of circ_0008882 was assessed by separation of nuclear and cytoplasmic RNAs. Nine circRNAs were associated with an increased risk for CRDs, while the relative expression of circ_0008882 was decreased after copper exposure in vitro and in vivo. Copper exposure stimulated 16HBE cells to release proinflammatory IL-6 and IL-8. The release of the cytokines was inhibited by overexpression of circ_0008882. These results suggest a role for circ_0008882 in the regulation of CRD associated inflammation following copper exposure.

Shared exposure liability of type 2 diabetes and other chronic conditions in the UK Biobank

AIMS

To investigate whether the cumulative exposure risks of incident T2D are shared with other common chronic diseases.

RESEARCH DESIGN AND METHODS

We first establish and report the cross-sectional prevalence, cross-sectional co-prevalence, and incidence of seven T2D-associated chronic diseases [hypertension, atrial fibrillation, coronary artery disease, obesity, chronic obstructive pulmonary disease (COPD), and chronic kidney and liver diseases] in the UK Biobank. We use published weights of genetic variants and exposure variables to derive the T2D polygenic (PGS) and polyexposure (PXS) risk scores and test their associations to incident diseases.

RESULTS

PXS was associated with higher levels of clinical risk factors including BMI, systolic blood pressure, blood glucose, triglycerides, and HbA1c in individuals without overt or diagnosed T2D. In addition to predicting incident T2D, PXS and PGS were significantly and positively associated with the incidence of all 7 other chronic diseases. There were 4% and 8% of individuals in the bottom deciles of PXS and PGS, respectively, who were prediabetic at baseline but had low risks of T2D and other chronic diseases. Compared to the remaining population, individuals in the top deciles of PGS and PXS had particularly high risks of developing chronic diseases. For instance, the hazard ratio of COPD and obesity for individuals in the top T2D PXS deciles was 2.82 (95% CI 2.39-3.35, P = 4.00 × 10-33) and 2.54 (95% CI 2.24-2.87, P = 9.86 × 10-50), respectively, compared to the remaining population. We also found that PXS and PGS were both significantly (P < 0.0001) and positively associated with the total number of incident diseases.

CONCLUSIONS

T2D shares polyexposure risks with other common chronic diseases. Individuals with an elevated genetic and non-genetic risk of T2D also have high risks of cardiovascular, liver, lung, and kidney diseases.

Dysregulation of mitochondrial complexes and dynamics by chronic cigarette smoke exposure Utilizing MitoQC reporter mice

Cigarette smoke (CS) is known to cause impaired mitophagy and mitochondrial dysregulation in the pathogenesis of chronic obstructive pulmonary disease (COPD)/emphysema. Mitochondrial complexes and dynamics are affected by acute CS exposure in lung epithelium and mouse lung. We hypothesize that chronic CS exposure (4 months) will induce lung mitochondrial dysregulation and abnormal mitophagy. In this study, we employed the mitoQC reporter mice, a mitochondrial reporter strain, which can reflect the mitophagy based on the fluorescence-tagged mitochondria. Chronic CS exposure induced lung inflammatory cell infiltration, airspace enlargement, and lung cellular senescence. We showed the higher occurrence of mitophagy (GFP/mCherry) in the lung cells by CS exposure, associated with more mitochondrial fluorescence signals (GFP⁺/mCherry⁺). After chronic CS exposure, the mitochondrial complexes and function related genes were inhibited, while protein levels of complexes I and III slightly changed. Additionally, chronic CS exposure down-regulated most of the mitochondrial dynamic markers at gene expression level, included mitochondrial fusion/fission and mitochondrial translocate/transfer markers. For the markers related to mitophagy, Pink1 and Parkin, decreased gene and protein levels of Parkin, and decreased gene expression of Pink1, were identified in the CS exposure group. Hence, CS-induced mitophagy is mediated by Pink1-Parkin independent mechanism. Thus, we have shown that the chronic CS epxosure dysregulated mitochondrial complexes and dynamics and induced mitophagy, using the state-of-the art mitoQC reporter mouse model. Our results suggested that dysregulated mitochondrial function and dynamics are associated with CS-induced lung injury and phenotypic development of chronic lung diseases, such as COPD/ emphysema.

Environmental hazards and demographic and clinical data of childhood interstitial lung diseases in a tertiary institute in Egypt

Background

The incidence of childhood interstitial lung diseases increased in the last years in Egypt. Changes in environmental and climatic conditions may be contributing factors. Also, raising birds at home increased in the past years due to financial issues. Other environmental factors include increased industries, traffic, and pollution. Our study aimed to assess the environmental hazards and the severity of childhood interstitial lung diseases.

Results

Sixty-five percent of patients with childhood interstitial lung diseases (chILD) were exposed to cigarette smoke; 45% were exposed to birds, 30% to industrial wastes, 20% to grass and pesticides, and 10% to animals.

Conclusions

Exposure to cigarette smoke and birds increases the risk of development of chILD.

Infrared Thermal Imaging of Patients With Acute Upper Respiratory Tract Infection: Mixed Methods Analysis

Background

Upper respiratory tract infection is a common disease of the respiratory system. Its incidence is very high, and it can even cause pandemics. Infrared thermal imaging (IRTI) can provide an objective and quantifiable reference for the visual diagnosis of people with acute respiratory tract infection, and it can function as an effective indicator of clinical diagnosis.

Objective

The aims of this study are to observe and analyze the infrared expression location and characteristics of patients with acute upper respiratory tract infection through IRTI technology and to clearly express the quantification of temperature, analyze the role of IRTI in acute upper respiratory tract diagnostic research, and understand the impact of IRTI in qualitative and quantitative research.

Methods

From December 2018 to February 2019, 154 patients with acute upper respiratory tract infection were randomly selected from the emergency department of the First Affiliated Hospital of Guangzhou Medical University. Among these patients, 73 were men and 81 were women. The subjects were divided into two groups according to the presence of fever, namely, fever and nonfever groups. Qualitative and quantitative analyses of the infrared thermal images were performed to compare the results before and after application of the technology.

Results

Using the method described in this paper, through the analysis of experimental data, we elucidated the role of IRTI in the diagnosis of acute upper respiratory tract infection, and we found that qualitative and quantitative IRTI analyses play important roles. Through the combination of theory and experimental data, the IRTI analysis showed good results in identifying acute upper respiratory tract infection.

Conclusions

IRTI technology plays an important role in identifying the infrared expression location and characteristics of patients with acute upper respiratory tract infection as well as in the quantification of clear expression of body temperature, and it provides an objective and quantifiable reference basis for elucidating the pathogenesis of these patients.

A novel humanized model of rheumatoid arthritis associated lung disease

Cigarette smoking has been implicated in the pathogenesis of seropositive rheumatoid arthritis (RA), as well as RA-associated lung disease. Fibrotic interstitial lung disease as well as emphysema occur in RA and cause substantial morbidity. We used arthritis-susceptible HLA-DQ8 transgenic mice to generate RA-associated lung disease. Mice were exposed to cigarette smoke (CS) prior to induction of arthritis, and subsequently injected with a low dose of bleomycin intra-tracheally to induce lung injury. Exposure of arthritic mice to both CS and bleomycin led to a significant reduction in lung compliance consistent with development of diffuse lung disease. Morphologic evaluation of the lung demonstrated areas of emphysematous change and co-existent fibrosis, consistent with a combined pattern of fibrosis and emphysema. These changes were accompanied by inflammatory cell infiltration and upregulation of fibrosis-associated genes. This humanized mouse model can serve as a valuable research tool to understand the pathogenesis of RA associated lung disease.

Influence of Indoor Temperature Exposure on Emergency Department Visits Due to Infectious and Non-Infectious Respiratory Diseases for Older People

Previous studies have demonstrated that outdoor temperature exposure was an important risk factor for respiratory diseases. However, no study investigates the effect of indoor temperature exposure on respiratory diseases and further assesses cumulative effect. The objective of this study is to study the cumulative effect of indoor temperature exposure on emergency department visits due to infectious (IRD) and non-infectious (NIRD) respiratory diseases among older adults. Subjects were collected from the Longitudinal Health Insurance Database in Taiwan. The cumulative degree hours (CDHs) was used to assess the cumulative effect of indoor temperature exposure. A distributed lag nonlinear model with quasi-Poisson function was used to analyze the association between CDHs and emergency department visits due to IRD and NIRD. For IRD, there was a significant risk at 27, 28, 29, 30, and 31 °C when the CDHs exceeded 69, 40, 14, 5, and 1 during the cooling season (May to October), respectively, and at 19, 20, 21, 22, and 23 °C when the CDHs exceeded 8, 1, 1, 35, and 62 during the heating season (November to April), respectively. For NIRD, there was a significant risk at 19, 20, 21, 22, and 23 °C when the CDHs exceeded 1, 1, 16, 36, and 52 during the heating season, respectively; the CDHs at 1 was only associated with the NIRD at 31 °C during the cooling season. Our data also indicated that the CDHs was lower among men than women. We conclude that the cumulative effects of indoor temperature exposure should be considered to reduce IRD risk in both cooling and heating seasons and NIRD risk in heating season and the cumulative effect on different gender.

Cigarette Smoking Increased Risk of Overall Mortality in Patients With Non-alcoholic Fatty Liver Disease: A Nationwide Population-Based Cohort Study

Background: The evidence suggests a detrimental effect of cigarette smoking on the progression of chronic liver disease. However, the impact of cigarette smoking on mortality among patients with non-alcoholic fatty liver disease (NAFLD) remain unclear. Methods: We used the National Health Examination Survey data collected during 2008-2009 to link the National Death Index to follow-up respondent survival. Diagnosis of NAFLD was based on a lipid accumulation product in participants without significant alcohol use or other liver diseases. Results: During 64,116 person-years of follow-up, 928 of 7,529 participants with NAFLD died, and the cumulative all-cause mortality was 14.5 per 1,000 person-years. In a Cox regression model adjusted for age, body mass index, alcohol intake, exercise, comorbidities, lipid profiles, and handgrip strength, current smoking increased the risk of mortality by 109% (adjusted hazard ratio (aHR): 2.09, 95% confidence interval [CI]: 1.18-3.71) compared with never smoker status in women, but showed only a trend toward harm among men (aHR: 1.41, 95% CI: 0.96-2.08). After controlling for potential confounders, smoking ≥10 pack-years continued to show a significant harmful effect on all-cause mortality among women (aHR: 5.40, 95% CI: 2.19-13.4), but not in men. Among women who drink alcohol ≥10 grams per day, current smoking (aHR: 13.8, 95% CI: 1.66-145) and smoking ≥10 pack-years (aHR: 310, 95% CI: 78-1,296) also significantly increased risk of death. Conclusion: This nationwide population-based study highlight a detrimental effect of cigarette smoking on mortality, with a similar but more definite association in women than in men with NAFLD.

Role of extracellular vesicles in cell-cell communication and inflammation following exposure to pulmonary toxicants

Extracellular vesicles (EVs) have emerged as key regulators of cell-cell communication during inflammatory responses to lung injury induced by diverse pulmonary toxicants including cigarette smoke, air pollutants, hyperoxia, acids, and endotoxin. Many lung cell types, including epithelial cells and endothelial cells, as well as infiltrating macrophages generate EVs. EVs appear to function by transporting cargo to recipient cells that, in most instances, promote their inflammatory activity. Biologically active cargo transported by EVs include miRNAs, cytokines/chemokines, damage-associated molecular patterns (DAMPs), tissue factor (TF)s, and caspases. Findings that EVs are taken up by target cells such as macrophages, and that this leads to increased proinflammatory functioning provide support for their role in the development of pathologies associated with toxicant exposure. Understanding the nature of EVs responding to toxic exposures and their cargo may lead to the development of novel therapeutic approaches to mitigating lung injury.

Cigarette smoke exposure alters phosphodiesterases in human structural lung cells

Cigarette smoke (CS), a highly complex mixture containing more than 4,000 compounds, causes aberrant cell responses leading to tissue damage around the airways and alveoli, which underlies various lung diseases. Phosphodiesterases (PDEs) are a family of enzymes that hydrolyze cyclic nucleotides. PDE inhibition induces bronchodilation, reduces the activation and recruitment of inflammatory cells, and the release of various cytokines. Currently, the selective PDE4 inhibitor roflumilast is an approved add-on treatment for patients with severe chronic obstructive pulmonary disease with chronic bronchitis and a history of frequent exacerbations. Additional selective PDE inhibitors are being tested in preclinical and clinical studies. However, the effect of chronic CS exposure on the expression of PDEs is unknown. Using mRNA isolated from nasal and bronchial brushes and lung tissues of never smokers and current smokers, we compared the gene expression of 25 PDE coding genes. Additionally, the expression and distribution of PDE3A and PDE4D in human lung tissues was examined. This study reveals that chronic CS exposure modulates the expression of various PDE members. Thus, CS exposure may change the levels of intracellular cyclic nucleotides and thereby impact the efficiency of PDE-targeted therapies.

Novel diterpenoid-type activators of the Keap1/Nrf2/ARE signaling pathway and their regulation of redox homeostasis

Oxidative stress is involved in the onset and progression of many human diseases. Activators of the Keap1/Nrf2/ARE pathway effectively inhibit the progression of oxidative stress-induced diseases. Herein, a small library of diterpenoids was established by means of phytochemical isolation, and chemical modification on naturally occurring molecules. The diterpenoids were subjected to a NAD(P)H: quinone reductase (QR) assay to evaluate its potential inhibition against oxidative stress. Sixteen diterpenoids were found to be novel potential activators of Nrf2-mediated defensive response. Of which, an isopimarane-type diterpenoid, sphaeropsidin A (SA), was identified as a potent activator of the Keap1/Nrf2/ARE pathway, and displayed approximately 5-folds potency than that of sulforaphane (SF). SA activated Nrf2 and its downstream cytoprotective genes through enhancing the stabilization of Nrf2 in a process involving PI3K, PKC, and PERK, as well as potentially interrupting Nrf2-Keap1 protein-protein interaction. In addition, SA conferred protection against sodium arsenite [As(III)]- and cigarette smoke extract (CSE)-induced redox imbalance and cytotoxicity in human lung epithelial cells, as wells as inhibited metronidazole (MTZ)-induced oxidative insult in Tg (krt4: NTR-hKikGR)^cy17 transgenic zebrafish and lipopolysaccharide (LPS)-induced oxidative damage in wild-type AB zebrafish. These results imply that SA is a lead compound for therapeutic agent against oxidative stress-induced diseases, and diterpenoid is a good resource for discovering drug candidates and leads of antioxidant therapy.

Electronic cigarette: A recent update of its toxic effects on humans

Electronic cigarettes (e-cigarettes), battery-powered and liquid-vaporizing devices, were invented to replace the conventional cigarette (c-cigarette) smoking for the sake of reducing the adverse effects on multiple organ systems that c-cigarettes have induced. Although some of the identified harmful components in e-cigarettes were alleged to be measured in lower quantity than those in c-cigarettes, researchers unveiled that the toxic effects of e-cigarettes should not be understated. This review is sought for an attempt to throw light on several typical types of e-cigarette components (tobacco-specific nitrosamines, carbonyl compounds, and volatile organic compounds) by revealing their possible impacts on human bodies through different action mechanisms characterized by alteration of specific biomarkers on cellular and molecular levels. In addition, this review is intended to draw the limelight that like c-cigarettes, e-cigarettes could also be accompanied with toxic effects on whole human body, which are especially apparent on respiratory system. From head to foot, from physical aspect to chemical aspect, from genotype to phenotype, potential alterations will take place upon the intake of the liquid aerosol.

Changes in pulmonary function of residents in Sanriku Seacoast following the tsunami disaster from the Great East Japan Earthquake

BACKGROUND

Residents in the district struck by the Great East Japan Earthquake Tsunami (GEJET) suffered from adverse living conditions and various pulmonary diseases.

OBJECTIVES

To evaluate the influence of GEJET, we performed serial assessment of pulmonary function of approximately 10,000 residents in the district struck by GEJET.

METHODS

Using a spirometer, we assessed the pulmonary function of approximately 10,000 residents older than 18 years in the Sanriku seacoast, which was struck by the tsunami. Measurements were performed in 2011 and 2012.

RESULTS

We compared FVC (forced vital capacity) % pred. and FEV1 (forced expiratory volume in 1second) % pred. of subjects between 2011 and 2012, by serial spirometry. Of the 7053 subjects studied, including 2611 men and 4442 women, FVC% pred. and FEV1% pred. were significantly higher in 2012 than in 2011. Physical indices including height, body weight and the body mass index (BMI) did not change significantly during this period. Smoking prevalence changed significantly between 2010, 2011, and 2012. Both FVC% pred. and FEV1% pred. of subjects who had quit smoking increased significantly on spirometry carried out in 2012, compared with those in 2011.

CONCLUSIONS

The pulmonary function expressed as FVC% pred. and FEV1% pred. were significantly higher in 2012 than in 2011 among the subjects studied. The changes in the smoking status may be one of the reasons for the increase in values observed. However, other undetermined factors during recovery from a disaster might have resulted in improved pulmonary function.

Pharmacogenetic study of seven polymorphisms in three nicotinic acetylcholine receptor subunits in smoking-cessation therapies

Smoking-cessation therapy reduces the risk of smoking-related diseases, but is successful only in a fraction of smokers. There is growing evidence that genetic variations in nicotinic acetylcholine receptor (nAChR) subunits influence the risk of nicotine dependence and the ability to quit smoking. To investigate the role of polymorphisms in nAChR genes on smoking quantity and the outcome of smoking-cessation therapies, we carried out an association study on 337 smokers who underwent pharmacotherapy with varenicline, bupropion, nicotine replacement therapy (NRT) alone, or NRT plus bupropion. Smoking habit and abstention were assessed from the number of cigarettes smoked per day (CPD) and the exhaled CO (eCO), at baseline and up to 12 months. We genotyped seven polymorphisms in genes encoding the nAChR subunits CHRNA4, CHRNA5, and CHRNB2. At baseline, both CPD and eCO were associated with polymorphisms in the CHRNA5 locus (rs503464, rs55853698, rs55781567 and rs16969968; P < 0.01). rs503464, a variant in the 5′-UTR of CHRNA5, was also associated with short-, mid- and long-term responses to therapy (P = 0.011, P = 0.0043, P = 0.020, respectively), although after correction for multiple testing only the association at the mid-term assessment remained significant (FDR = 0.03). These data support the role of individual genetic makeup in the ability to quit smoking.

MAP3K19 Is Overexpressed in COPD and Is a Central Mediator of Cigarette Smoke-Induced Pulmonary Inflammation and Lower Airway Destruction

Chronic obstructive pulmonary disease (COPD) is characterized by persistent airflow limitation and lung inflammation resulting in a progressive decline in lung function whose principle cause is cigarette smoke. MAP3K19 is a novel kinase expressed predominantly by alveolar and interstitial macrophages and bronchial epithelial cells in the lung. We found that MAP3K19 mRNA was overexpressed in a limited sampling of lung tissue from COPD patients, and a closer examination found it to be overexpressed in bronchoalveolar macrophages from COPD patients, as well as the bronchial epithelium and inflammatory cells in the lamina propria. We further found MAP3K19 to be induced in various cell lines upon environmental stress, such as cigarette smoke, oxidative and osmotic stress. Exogenous expression of MAP3K19 in cells caused an upregulation of transcriptionally active NF-κB, and secretion of the chemokines CXCL-8, CCL-20 and CCL-7. Inhibition of MAP3K19 activity by siRNA or small molecular weight inhibitors caused a decrease in cigarette smoke-induced inflammation in various murine models, which included a decrease in pulmonary neutrophilia and KC levels. In a chronic cigarette smoke model, inhibition of MAP3K19 significantly attenuated emphysematous changes in airway parenchyma. Finally, in a viral exacerbation model, mice exposed to cigarette smoke and influenza A virus showed a decrease in pulmonary neutrophilia, pro-inflammatory cytokines and viral load upon inhibition of MAP3K19. Collectively, these results suggest that inhibition of MAP3K19 may represent a novel strategy to target COPD that promises to have a potential therapeutic benefit for patients.

Drug-related pneumonitis during mammalian target of rapamycin inhibitor therapy in patients with neuroendocrine tumors: a radiographic pattern-based approach

PURPOSE

The purpose of this study was to investigate the incidence of drug-related pneumonitis during mammalian target of rapamycin (mTOR) inhibitor therapy in patients with neuroendocrine tumours (NET) and characterise radiographic patterns of pneumonitis.

METHODS

Sixty-six patients (39 males, 27 females, age: 22-79 years) with advanced NET treated with mTOR inhibitor, everolimus, were retrospectively studied. Chest computed tomography scans during therapy were reviewed for abnormalities suspicious for drug-related pneumonitis by an independent review of two radiologists. Extent, distributions, and specific findings were evaluated in cases positive for pneumonitis. Radiographic patterns of pneumonitis were classified using the American Thoracic Society/European Respiratory Society classification of interstitial pneumonia.

RESULTS

Drug-related pneumonitis was radiographically detected in 14 patients (21%). Time from the initiation of therapy to pneumonitis was within 6 months of therapy in 10 patients (71%), while it ranged from 1.0 to 27.7 months. Pneumonitis was more common in patients who had never smoked (p=0.03). Lower lungs were more extensively involved than upper and middle lungs. Peripheral and lower distributions were most common (n=8), followed by peripheral and multifocal distributions (n=3). Ground glass and reticular opacities were present in all cases, with consolidation in eight cases. The radiographic pattern of pneumonitis was classified as cryptogenic organising pneumonia (COP) pattern in eight patients, non-specific interstitial pneumonia (NSIP) pattern in five, and hypersensitivity pneumonitis pattern in one patient.

CONCLUSION

Drug-related pneumonitis was noted in 21% of the advanced NET patients treated with everolimus. Radiographic pattern of pneumonitis was most commonly COP pattern, followed by NSIP pattern.

Changes in the expression and protein level of matrix metalloproteinases after exposure to waterpipe tobacco smoke

Waterpipe smoking has become a worldwide epidemic with health consequences that only now are beginning to be understood fully. Because waterpipe use involves inhaling a large volume of toxicant-laden smoke that can cause inflammation, some health consequences may include inflammation-mediated lung injury. Excess matrix metalloproteinase expression is a key step in the etiology of toxicant exposure-driven inflammation and injury. In this study, changes in the level and mRNA of major matrix metalloproteinases (MMP-1, -9, and -12) in the lungs of mice following exposure to waterpipe smoke were investigated. Balb/c mice were exposed to waterpipe smoke for one hour daily, over a period of 2 or 8 weeks. Control mice were exposed to fresh air only. ELISA and real-time PCR techniques were used to determine the protein and mRNA levels of MMP-1, -9, and -12 in the lungs. Our findings showed that MMP-1, -9, and -12 levels in the lung significantly increased after both 2 (p < 0.05) and 8 weeks (p < 0.01) exposures. Similarly, RT-PCR findings showed that mRNA of those proteinases significantly increased following 2 (p < 0.01) and 8 weeks (p < 0.001) exposures. In conclusion, waterpipe smoking is associated strongly with lung injury as measured by elevation in the expression of MMPs in the lung tissue.

Human adipose-derived stem cells ameliorate cigarette smoke-induced murine myelosuppression via secretion of TSG-6

OBJECTIVE

Bone marrow-derived hematopoietic stem and progenitor cells (HSC/HPC) are critical to homeostasis and tissue repair. The aims of this study were to delineate the myelotoxicity of cigarette smoking (CS) in a murine model, to explore human adipose-derived stem cells (hASC) as a novel approach to mitigate this toxicity, and to identify key mediating factors for ASC activities.

METHODS

C57BL/6 mice were exposed to CS with or without i.v. injection of regular or siRNA-transfected hASC. For in vitro experiments, cigarette smoke extract was used to mimic the toxicity of CS exposure. Analysis of bone marrow HPC was performed both by flow cytometry and colony-forming unit assays.

RESULTS

In this study, we demonstrate that as few as 3 days of CS exposure results in marked cycling arrest and diminished clonogenic capacity of HPC, followed by depletion of phenotypically defined HSC/HPC. Intravenous injection of hASC substantially ameliorated both acute and chronic CS-induced myelosuppression. This effect was specifically dependent on the anti-inflammatory factor TSG-6, which is induced from xenografted hASC, primarily located in the lung and capable of responding to host inflammatory signals. Gene expression analysis within bone marrow HSC/HPC revealed several specific signaling molecules altered by CS and normalized by hASC.

CONCLUSION

Our results suggest that systemic administration of hASC or TSG-6 may be novel approaches to reverse CS-induced myelosuppression.

Respiratory tract infections in the military environment

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Soldiers in combat zones are at risk of contracting respiratory infections.

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Troops deployed to the harsh environment have high rates of respiratory symptoms.

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Over 40% of soldiers’ respiratory illnesses have been due to unknown causative agents.

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Limited diagnostic capabilities make it difficult to estimate the number of cases.

Military personnel fighting in contemporary battlefields as well as those participating in combat training are at risk of contracting respiratory infections. Epidemiological studies have demonstrated that soldiers deployed to the harsh environment have higher rates of newly reported respiratory symptoms than non-deployers. Acute respiratory diseases are the principle reason for outpatient treatment and hospitalization among military personnel, with an incidence exceeding that of the adult civilian population by up to three-fold. Adenoviruses, influenza A and B viruses, Streptococcus pneumoniae, Streptococcus pyogenes, coronaviruses and rhinoviruses have been identified as the main causes of acute respiratory infections among the military population. Although infective pathogens have been extensively studied, a significant proportion of illnesses (over 40%) have been due to unknown causative agents. Other health hazards, which can lead to respiratory illnesses among troops, are extreme air temperatures, desert dust, emissions from burn pits, industrial pollutants, and airborne contaminants originating from degraded soil. Limited diagnostic capabilities, especially inside the area of operations, make it difficult to accurately estimate the exact number of respiratory diseases in the military environment. The aim of the study was to discuss the occurrence of respiratory tract infections in army personnel, existing risk factors and preventive measures.

Functional impact of a spectrum of interstitial lung abnormalities in rheumatoid arthritis

BACKGROUND

Approximately 10% of patients with rheumatoid arthritis (RA) have interstitial lung disease (ILD), and one-third have subclinical ILD on chest CT scan. In this study, we aimed to further characterize functional decrements in a spectrum of RA-associated ILD.

METHODS

All subjects were enrolled in the Brigham and Women's Hospital Rheumatoid Arthritis Sequential Study (BRASS). The presence of interstitial lung abnormalities (ILAs) on clinically indicated chest CT scans was determined using a previously validated sequential reading method. Univariate and multivariate analyses were used to assess the association between degree of ILAs and physiologic, functional, and demographic variables of interest.

RESULTS

Of 1,145 BRASS subjects, 91 subjects (8%) were included in this study. Twelve had radiologically severe ILAs, 34 had ILAs, and 38 had no ILAs on CT scan. Subjects with radiologically severe ILAs were older (P = .0037), had increased respiratory symptoms (cough, P = .027; dyspnea, P = .010), and more severe RA disease (rheumatoid factor, P = .018; total swollen joints, P = .046) compared with subjects with no ILAs. Participants also had a trend toward having an increased smoking history (P = .16) and having lower FVC % predicted (77% vs 94%, P = .097) and diffusion capacity of carbon monoxide % predicted (52% vs 77%, P = .068). Similar but attenuated increases in respiratory symptoms, functional decrements, and RA disease severity were observed in subjects with ILAs compared with those with no ILAs.

CONCLUSIONS

We have shown that patients with RA have varying degrees of ILAs that are associated with a spectrum of functional and physiologic decrements. Our findings suggest that improved risk stratification and detection of ILAs will provide a therapeutic window that could improve RA-ILD outcomes.

Tobacco smoking increases immune activation and impairs T-cell function in HIV infected patients on antiretrovirals: a cross-sectional pilot study

Background

The influence of tobacco smoking on the immune system of HIV infected individuals is largely unknown. We investigated the impact of tobacco smoking on immune activation, microbial translocation, immune exhaustion and T-cell function in HIV infected individuals.

Method

HIV infected smokers and non-smokers (n = 25 each) with documented viral suppression on combination antiretroviral therapy and HIV uninfected smokers and non-smokers (n = 15 each) were enrolled. Markers of immune activation (CD38 and HLA-DR) and immune exhaustion (PD1, Tim3 and CTLA4) were analyzed in peripheral blood mononuclear cells (PBMCs) by flow cytometry. Plasma markers of microbial translocation (soluble-CD14 - sCD14 and lipopolysaccharide - LPS) were measured. Antigen specific functions of CD4+ and CD8+ T-cells were measured, by flow cytometry, in PBMCs after 6 hours stimulation with Cytomegalovirus, Epstein-Barr virus and Influenza Virus (CEF) peptide pool.

Results

Compared to non-smokers, smokers of HIV infected and uninfected groups showed significantly higher CD4+ and CD8+ T-cell activation with increased frequencies of CD38+HLA-DR+ cells with a higher magnitude in HIV infected smokers. Expressions of immune exhaustion markers (PD1, Tim3 and CTLA4) either alone or in combinations were significantly higher in smokers, especially on CD4+ T-cells. Compared to HIV uninfected non-smokers, microbial translocation (sCD14 and LPS) was higher in smokers of both groups and directly correlated with CD4+ and CD8+ T-cell activation. Antigen specific T-cell function showed significantly lower cytokine response of CD4+ and CD8+ T-cells to CEF peptide-pool stimulation in smokers of both HIV infected and uninfected groups.

Conclusions

Our results suggest that smoking and HIV infection independently influence T-cell immune activation and function and together they present the worst immune profile. Since smoking is widespread among HIV infected individuals, studies are warranted to further evaluate the cumulative effect of smoking on impairment of the immune system and accelerated disease progression.

Pathophysiology of tobacco smoke exposure: recent insights from comparative and redox proteomics

First-hand and second-hand tobacco smoke are causally linked to a huge number of deaths and are responsible for a broad spectrum of pathologies such as cancer, cardiovascular, respiratory, and eye diseases as well as adverse effects on female reproductive function. Cigarette smoke is a complex mixture of thousands of different chemical species, which exert their negative effects on macromolecules and biochemical pathways, both directly and indirectly. Many compounds can act as oxidants, pro-inflammatory agents, carcinogens, or a combination of these. The redox behavior of cigarette smoke has many implications for smoke related diseases. Reactive oxygen and nitrogen species (both radicals and non-radicals), reactive carbonyl compounds, and other species may induce oxidative damage in almost all the biological macromolecules, compromising their structure and/or function. Different quantitative and redox proteomic approaches have been applied in vitro and in vivo to evaluate, respectively, changes in protein expression and specific oxidative protein modifications induced by exposure to cigarette smoke and are overviewed in this review. Many gel-based and gel-free proteomic techniques have already been used successfully to obtain clues about smoke effects on different proteins in cell cultures, animal models, and humans. The further implementation with other sensitive screening techniques could be useful to integrate the comprehension of cigarette smoke effects on human health. In particular, the redox proteomic approach may also help identify biomarkers of exposure to tobacco smoke useful for preventing these effects or potentially predictive of the onset and/or progression of smoking-induced diseases as well as potential targets for therapeutic strategies.

A roadmap to promote clinical and translational research in rheumatoid arthritis-associated interstitial lung disease

Rheumatoid arthritis (RA) is a systemic inflammatory disorder affecting approximately 1.3 million adults in the United States. Approximately 10% of these individuals with RA have clinically evident interstitial lung disease (RA-ILD), and an additional one-third demonstrate subclinical ILD on chest CT scan. The risk of death for individuals with RA-ILD is three times higher than for patients with RA without ILD, with a median survival after ILD diagnosis of only 2.6 years. Despite the high prevalence and mortality of RA-ILD, little is known about its molecular features and its natural history. At present, we lack a standard validated approach to the definition, diagnosis, risk stratification, and management of RA-ILD. In this perspective, we discuss the importance of clinical and translational research and how ongoing research efforts can address important gaps in our knowledge over the next few years. Furthermore, recommendations are made to design multicenter collaborative studies that will expedite the development of clinical trials designed to decrease the significant morbidity and mortality associated with RA-ILD.

Implications of tobacco smoking on the oral health of older adults

Cigarette smoking is the foremost health risk issue affecting individuals of all age groups globally. It specifically influences the geriatric population as a result of chronic exposure to toxins. Its role in various systemic and oral diseases including cancer, premalignant lesions, periodontitis, tooth loss, dental caries and implant failures is well established. Smoking causes immuno-inflammatory imbalances resulting in increased oxidative stress in the body. The latter hastens the immunosenescence and inflammaging process, which increases the susceptibility to infections. Thus, implementation of smoking cessation programs among older adults is imperative to prevent the development and progression of oral and systemic diseases. The present review focuses on smoking-associated oral health problems in older adults, and the steps required for cessation of the habit.

Bronchiolitis: adopting a unifying definition and a comprehensive etiological classification

Bronchiolitis is an inflammatory and potentially fibrosing condition affecting mainly the intralobular conducting and transitional small airways. Secondary bronchiolitis participates in disease process of the airways and/or the surrounding lobular structures in the setting of several already defined clinical entities, mostly of known etiology, and occurs commonly. Primary or idiopathic bronchiolitis dominates and characterizes distinct clinical entities, all of unknown etiology, and occurs rarely. Secondary bronchiolitis regards infections, hypersensitivity disorders, the whole spectrum of smoking-related disorders, toxic fumes and gas inhalation, chronic aspiration, particle inhalation, drug-induced bronchiolar toxicities, sarcoidosis and neoplasms. Idiopathic or primary bronchiolitis defines clinicopathologic entities sufficiently different to be designated as separate disease entities and include cryptogenic constrictive bronchiolitis, diffuse panbronchiolitis, diffuse idiopathic pulmonary neuroendocrine cell hyperplasia, neuroendocrine hyperplasia in infants, bronchiolitis obliterans syndrome in lung and allogeneic hematopoietic cell transplantation, connective tissue disorders, inflammatory bowel disease and bronchiolitis obliterans organizing pneumonia. Most of the above are pathological descriptions used as clinical diagnosis. Acute bronchiolitis, though potentially life threatening, usually regresses. Any etiology chronic bronchiolitis contributes to morbidity and/or mortality if it persists and/or progresses to diffuse airway narrowing and distortion or complete obliteration. Bronchiolitis in specific settings leads to bronchiolectasis, resulting in bronchiectasis.

An omics strategy for discovering pulmonary biomarkers potentially relevant to the evaluation of tobacco products

Smoking is known to cause serious lung diseases including chronic bronchitis, chronic obstructive lung disease, obstruction of small airways, emphysema and cancer. Tobacco smoke is a complex chemical aerosol containing at least 8000 chemical constituents, either tobacco derived or added by tobacco product manufacturers. Identification of all of the toxic agents in tobacco smoke is challenging, and efforts to understand the mechanisms by which tobacco use causes disease will be informed by new biomarkers of exposure and harm. In 2009, President Obama signed into law the Family Smoking Prevention and Tobacco Control Act granting the US FDA the authority to regulate tobacco products to protect public health. This perspective article presents the background, rationale and strategy for using omics technologies to develop new biomarkers, which may be of interest to the FDA when implementing the Family Smoking Prevention and Tobacco Control Act.

Associations between smoking and tooth loss according to the reason for tooth loss: the Buffalo OsteoPerio Study

BACKGROUND

Smoking is associated with tooth loss. However, smoking's relationship to the specific reason for tooth loss in postmenopausal women is unknown.

METHODS

Postmenopausal women (n = 1,106) who joined a Women's Health Initiative ancillary study (The Buffalo OsteoPerio Study) underwent oral examinations for assessment of the number of missing teeth, and they reported the reasons for tooth loss. The authors obtained information about smoking status via a self-administered questionnaire. The authors calculated odds ratios (ORs) and 95 percent confidence intervals (CIs) by means of logistic regression to assess smoking's association with overall tooth loss, as well as with tooth loss due to periodontal disease (PD) and with tooth loss due to caries.

RESULTS

After adjusting for age, education, income, body mass index, history of diabetes diagnosis, calcium supplement use and dental visit frequency, the authors found that heavy smokers (≥ 26 pack-years) were significantly more likely to report having experienced tooth loss compared with never smokers (OR = 1.82; 95 percent CI, 1.10-3.00). Smoking status, packs smoked per day, years of smoking, pack-years and years since quitting smoking were significantly associated with tooth loss due to PD. For pack-years, the association for heavy smokers compared with that for never smokers was OR = 6.83 (95 percent CI, 3.40 -13.72). The study results showed no significant associations between smoking and tooth loss due to caries.

CONCLUSIONS AND PRACTICAL IMPLICATIONS

Smoking may be a major factor in tooth loss due to PD. However, smoking appears to be a less important factor in tooth loss due to caries. Further study is needed to explore the etiologies by which smoking is associated with different types of tooth loss. Dentists should counsel their patients about the impact of smoking on oral health, including the risk of experiencing tooth loss due to PD.

Highlights of the Brazilian Thoracic Association guidelines for interstitial lung diseases

Interstitial lung diseases (ILDs) are heterogeneous disorders, involving a large number of conditions, the approach to which continues to pose an enormous challenge for pulmonologists. The 2012 Brazilian Thoracic Association ILD Guidelines were established in order to provide Brazilian pulmonologists with an instrument that can facilitate the management of patients with ILDs, standardizing the criteria used for the diagnosis of different conditions and offering guidance on the best treatment in various situations. The objective of this article was to briefly describe the highlights of those guidelines.

Cyto-genotoxic effects of smoke from commercial filter and non-filter cigarettes on human bronchial and pulmonary cells

Cigarette smoke is a complex mixture of chemicals, some of which are known as carcinogens. The cyto-genotoxic effects of cigarette-smoke extract (CSE) from commercial cigarettes without (A and B) and with filter (C and D) were evaluated at different CSE concentrations on A549 and BEAS-2B cells. The particle content of the cigarette smoke and the metal composition of the CSE were also analyzed. The cells were exposed to 1-10% of the CSE from one cigarette per experiment. Cytotoxicity was evaluated by use of the MTT assay after 24h, and the lactate dehydrogenase (LDH) assay after 30min and 24h. The Fpg-modified comet assay was used to evaluate direct-oxidative DNA damage on cells exposed for 30min. As expected, unfiltered cigarette smoke (particularly from the B cigarette) contained a higher number of particles than filtered smoke. With smoke extract from the B cigarette we found a decrease in cell viability only in BEAS-2B cells. The results of the LDH test showed membrane damage for B-cigarette smoke extract, particularly in BEAS-2B cells. Extracts from unfiltered cigarette smoke induced significant direct DNA damage, to a larger extent in A549 cells. Filtered cigarette-smoke extract induced a significant direct DNA damage at 5-10%. A significant induction of oxidative DNA damage was found at the highest CSE concentration in both cell types (by smoke extracts from B and C cigarettes in A549 cells, and from A and D cigarettes in BEAS-2B cells). Smoke extracts from filter cigarettes induced less direct DNA damage than those from unfiltered cigarettes in A549 cells, probably due to a protective effect of filter. In BEAS-2B cells the smoke extract from the B-cigarette showed the highest genotoxic effect, with a concentration-dependent trend. These findings show a higher cyto-genotoxicity for smoke extracts from the B-cigarette and oxidative effects for those from the A and D cigarettes, particularly in BEAS-2B cells. Moreover, there was a higher responsiveness of A549 cells to genotoxic insult of CSE, and a cigarette-dependent genotoxicity in BEAS-2B cells. Our experimental model demonstrated to be suitable to sensitively detect early genotoxic response of different lung-cell types to non-cytotoxic concentrations of complex inhalable mixtures.

Cigarette smoke-induced accumulation of lung dendritic cells is interleukin-1α-dependent in mice

Background

Evidence suggests that dendritic cells accumulate in the lungs of COPD patients and correlate with disease severity. We investigated the importance of IL-1R1 and its ligands IL-1α and β to dendritic cell accumulation and maturation in response to cigarette smoke exposure.

Methods

Mice were exposed to cigarette smoke using a whole body smoke exposure system. IL-1R1-, TLR4-, and IL-1α-deficient mice, as well as anti-IL-1α and anti-IL-1β blocking antibodies were used to study the importance of IL-1R1 and TLR4 to dendritic cell accumulation and activation.

Results

Acute and chronic cigarette smoke exposure led to increased frequency of lung dendritic cells. Accumulation and activation of dendritic cells was IL-1R1/IL-1α dependent, but TLR4- and IL-1β-independent. Corroborating the cellular data, expression of CCL20, a potent dendritic cells chemoattractant, was IL-1R1/IL-1α-dependent. Studies using IL-1R1 bone marrow-chimeric mice revealed the importance of IL-1R1 signaling on lung structural cells for CCL20 expression. Consistent with the importance of dendritic cells in T cell activation, we observed decreased CD4⁺ and CD8⁺ T cell activation in cigarette smoke-exposed IL-1R1-deficient mice.

Conclusion

Our findings convey the importance of IL-1R1/IL-1α to the recruitment and activation of dendritic cells in response to cigarette smoke exposure.

Subclinical interstitial lung disease: why you should care

The widespread use of high-resolution computed tomography in clinical and research settings has increased the detection of interstitial lung abnormalities (ILA) in asymptomatic and undiagnosed individuals. We reported that in smokers, ILA were present in about 1 of every 12 high-resolution computed tomographic scans; however, the long-term significance of these subclinical changes remains unclear. Studies in families affected with pulmonary fibrosis, smokers with chronic obstructive pulmonary disease, and patients with inflammatory lung disease have shown that asymptomatic and undiagnosed individuals with ILA have reductions in lung volume, functional limitations, increased pulmonary symptoms, histopathologic changes, and molecular profiles similar to those observed in patients with clinically significant interstitial lung disease (ILD). These findings suggest that, in select at-risk populations, ILA may represent early stages of pulmonary fibrosis or subclinical ILD. The growing interest surrounding this topic is motivated by our poor understanding of the inciting events and natural history of ILD, coupled with a lack of effective therapies. In this perspective, we outline past and current research focused on validating radiologic, physiological, and molecular methods to detect subclinical ILD. We discuss the limitations of the available cross-sectional studies and the need for future longitudinal studies to determine the prognostic and therapeutic implications of subclinical ILD in populations at risk of developing clinically significant ILD.

Red blood cells protect albumin from cigarette smoke-induced oxidation

Different studies reported the presence of oxidized (carbonylated) albumin in the extravascular pool, but not in the intravascular one of cigarette smokers. In this study we attempted to explain this apparent discrepancy exposing human serum albumin (HSA) to aqueous cigarette smoke extract (CSE). CSE induces HSA carbonylation and oxidation of the HSA Cys34 sulfhydryl group. An antioxidant action of glutathione, cysteine, and its synthetic derivative N-acetylcysteine was observed only at supra-physiological concentrations, suggesting that physiological (plasma) concentrations of glutathione and cysteine in the low micromolar range are ineffective in preventing cigarette smoke-induced oxidation of HSA. Differently, human erythrocytes resulted to be protective towards CSE-induced oxidation (carbonylation and thiol oxidation) of both HSA and total human plasma proteins.

Smoking-related interstitial lung diseases

Cigarette smoke, a toxic collection of thousands of chemicals generated from combustion of tobacco, is recognized as the primary causative agent of certain diffuse interstitial and bronchiolar lung diseases. Most patients afflicted with these disorders are cigarette smokers, and smoking cessation has been shown to be capable of inducing disease remission and should occupy a pivotal role in the management of all smokers with these diffuse lung diseases. The role of pharmacotherapy with corticosteroids or other immunomodulating agents is not well established but may be considered in patients with progressive forms of smoking-related interstitial lung diseases.

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.

Humic acid enhances cigarette smoke-induced lung emphysema in mice and IL-8 release of human monocytes

Tobacco smoke is the main factor in the etiology of lung emphysema. Generally prolonged, substantial exposure is required to develop the disease. Humic acid is a major component of cigarette smoke that accumulates in smokers' lungs over time and induces tissue damage.

OBJECTIVES

To investigate whether humic acid pre-loading potentiates the development of cigarette smoke-induced lung emphysema in mice and increases IL-8 release by human monocytes.

METHODS

C57BL/6J mice received humic acid or aqueous vehicle by tracheal installation on day 0 and day 7. From day 21 to day 84, the mice were exposed to cigarette smoke or clean air for 5 days/week. Twenty-four hours after the last exposure we determined leukocytes in lung lavage, heart hypertrophy and alveolar wall destruction. Human monocytes were incubated with cigarette smoke extract (CSE), humic acid or the combination overnight.

RESULTS

Humic acid nor cigarette smoke caused alveolar wall destruction within two months. Interestingly, the combination did induce lung emphysema. Humic acid, cigarette smoke or the combination did not change leukocyte types and numbers in lung lavage fluid, but the combination caused peribronchiolar and perivascular lymphocyte infiltration. Humic acid treatment resulted in a high proportion of alveolar macrophages heavily loaded with intracellular granula. Humic acid also induces the release of IL-8 from human monocytes and enhances the CSE-induced IL-8 release.

CONCLUSIONS

Humic acid deposition in the lungs potentiates the development of cigarette smoke-induced interstitial inflammation and lung emphysema. Moreover, humic acid promotes IL-8 release from human monocytes. Since humic acid accumulates steadily in the lungs of smokers, this may provide an explanation for the natural history on late onset of this disease. The model described here offers a novel way to study emphysema and may direct the search for new therapeutic approaches.

Assessment of smoking behaviour in the dental setting. A study comparing self-reported questionnaire data and exhaled carbon monoxide levels

The present study validated the accuracy of data from a self-reported questionnaire on smoking behaviour with the use of exhaled carbon monoxide (CO) level measurements in two groups of patients. Group 1 included patients referred to an oral medicine unit, whereas group 2 was recruited from the daily outpatient service. All patients filled in a standardized questionnaire regarding their current and former smoking habits. Additionally, exhaled CO levels were measured using a monitor. A total of 121 patients were included in group 1, and 116 patients were included in group 2. The mean value of exhaled CO was 7.6 ppm in the first group and 9.2 ppm in the second group. The mean CO values did not statistically significantly differ between the two groups. The two exhaled CO level measurements taken for each patient exhibited very good correlation (Spearman's coefficient of 0.9857). Smokers had a mean difference of exhaled CO values of 13.95 ppm (p < 0.001) compared to non-smokers adjusted for the first or second group. The consumption of one additional pack year resulted in an increase in CO values of 0.16 ppm (p = 0.003). The consumption of one additional cigarette per day elevated the CO measurements by 0.88 ppm (p < 0.001). Based on these results, the correlations between the self-reported smoking habits and exhaled CO values are robust and highly reproducible. CO monitors may offer a non-invasive method to objectively assess current smoking behaviour and to monitor tobacco use cessation attempts in the dental setting.

Desquamative interstitial pneumonia as the initial manifestation of systemic sclerosis

Interstitial lung disease (ILD) is a frequent pulmonary complication of systemic sclerosis (SSc), and nonspecific interstitial pneumonia is the most commonly recognized pattern of lung injury in these patients. In this report, we describe a never-smoker female presenting with Raynaud phenomenon and ILD that demonstrated desquamative interstitial pneumonia (DIP) on surgical lung biopsy. After 8 months, she was diagnosed with pulmonary hypertension at which time clinical examinations and serologic findings established the diagnosis of SSc. This case report expands the spectrum of patterns of ILD seen in association with SSc to include DIP.

Patients' awareness of the potential benefit of smoking cessation. A study evaluating self-reported and clinical data from patients referred to an oral medicine unit

The present study analyzed history of smoking and willingness to quit smoking in patients referred for diagnosis and treatment of different oral mucosal lesions. Prior to the initial clinical examination, patients filled in a standardized questionnaire regarding their current and former smoking habits and willingness to quit. Definitive diagnoses were classified into three groups (benign/reactive lesions, premalignant lesions and conditions, and malignant diseases) and correlated with the self-reported data in the questionnaires. Of the 980 patients included, 514 (52%) described themselves as never smokers, 202 (21%) as former smokers, and 264 (27%) as current smokers. In the group of current smokers, 23% thought their premalignant lesions/conditions were related to their smoking habit, but only 15% of the patients with malignant mucosal diseases saw that correlation. Only 14% of the smokers wanted to commence smoking cessation within the next 30 days. Patients with malignant diseases (31%) showed greater willingness to quit than patients diagnosed with benign/reactive lesions (11%). Future clinical studies should attempt (1) to enhance patients' awareness of the negative impact of smoking on the oral mucosa and (2) to increase willingness to quit in smokers referred to a dental/oral medicine setting.