Chronic Pulmonary Inflammation Research Articles

Aurintricarboxylic acid mitigates cigarette smoke extract induced oxidative stress and pulmonary inflammation via inhibition of NF-ҡB/p65 signaling

Cigarette smoke (CS) induced emphysema and chronic pulmonary inflammation are major comorbidities of chronic obstructive pulmonary disease (COPD), a major cause of morbidity and mortality worldwide. CS exposure exacerbates pulmonary inflammation and compromises immunity to various infections. Aurintricarboxylic acid (ATA) is a polyanionic aromatic compound especially recognized for its anti-inflammatory, nucleic acid, and protein interaction inhibition properties. The study was designed to investigate the anti-inflammatory role of ATA against cigarette smoke extract (CSE) induced pulmonary inflammation. Nicotine concentration was quantified in CSE by UPLC/MS technique. In vitro, fluorescence microscopy, and flow cytometry was performed in CSE stimulated alveolar epithelial cells to determine the effect of ATA on oxidative stress-mediated cellular apoptosis. In vivo, pulmonary inflammation was induced in male Wistar rats via a modified non-invasive intratracheal instillation of cigarette smoke extract (100 µl/animal) twice a week for 8 weeks and post-treated with ATA (10 mg/kg) intraperitoneally for 15 days. Lung homogenates were assessed for MDA and GSH. Lung tissues were subjected to western blotting and histopathological analysis. As result, ATA reduced CSE-induced chromatin condensation, fragmentation, cellular apoptosis in alveolar epithelial cells, and apoptotic biomarkers expression including BAX and Caspase-3 in the lungs. ATA reduced inflammation by normalizing redox balance reflected by MDA/GSH levels. ATA obviated airspace enlargement, fiber deposition, and immune cell infiltration. Reduced inflammation was accompanied by inhibition of inflammatory biomarkers TNF-α, TNFR1, TWEAK, and NF-ҡB/p65 activation and nuclear translocation. ATA efficaciously diminished the oxidative stress and pulmonary inflammation associated with lung pathogenesis through TNF-α/TNFR1/NF-ҡB/p65 signaling pathway. HIGHLIGHTS ATA treatment attenuates CSE-stimulated chromatin condensation, fragmentation, and cellular apoptosis in alveolar epithelial cells. ATA treatment inhibits CSE stimulated activation and nuclear translocation of NF-ҡB/p65. ATA treatment diminishes CSE-induced oxidant injury, apoptosis, and emphysema-like phenotypic changes in the lungs. ATA inhibits lung inflammation via suppression of the NF-ҡB/p65 signaling pathway.

Regulatory roles of external cholesterol in human airway epithelial mitochondrial function through STARD3 signalling.

BackgroundHypercholesterolemia is found in patients with chronic lung inflammation, during which airway epithelial cells play important roles in maintenance of inflammatory responses to pathogens. The present study aims at molecular mechanisms by which cholesterol changes airway epithelial sensitivity in response to smoking.MethodsHuman bronchial epithelial cells (HBEs) were stimulated with cigarette smoke extract (CSE) and mice were exposed to CS/lipopolysaccharide (LPS) as models in vitro and in vivo. Severe COPD patients and healthy volunteers were also enrolled and the level of cholesterol in plasma was detected by metabolomics. Filipin III and elisa kits were used to stain free cholesterol. Mitochondrial function was detected by mitotracker green, mitotracker green, and Seahorse. Mitochondrial morphology was detected by high content screening and electron microscopy. The mRNA and protein levels of mitochondrial dynamics‐related proteins were detected by RT‐qPCR and Western blot,respectively. BODIPY 493/503 was used to stain lipid droplets. Lipidomics was used to detect intracellular lipid components. The mRNA level of interleukin (IL)‐6 and IL‐8 were detected by RT‐qPCR.ResultsWe found that the cholesterol overload was associated with chronic obstructive pulmonary disease (COPD) and airway epithelia‐driven inflammation, evidenced by hypercholesterolemia in patients with COPD and preclinical models, alteration of lipid metabolism‐associated genes in CSE‐induced airway epithelia and production of ILs. External cholesterol altered airway epithelial sensitivity of inflammation in response to CSE, through the regulation of STARD3‐MFN2 pathway, cholesterol re‐distribution, altered transport and accumulation of cholesterol, activities of lipid transport regulators and disorder of mitochondrial function and dynamics. MFN2 down‐regulation increased airway epithelial sensitivity and production of ILs after smoking, at least partially by injuring fatty acid oxidation and activating mTOR phosphorylation.ConclusionsOur data provide new insights for understanding molecular mechanisms of cholesterol‐altered airway epithelial inflammation and for developing diagnostic biomarkers and therapeutic targets to improve patient outcomes.

Exploring the Change of Host and Microorganism in Chronic Obstructive Pulmonary Disease Patients Based on Metagenomic and Metatranscriptomic Sequencing.

BackgroundChronic obstructive pulmonary disease (COPD) is a universal respiratory disease resulting from the complex interactions between genes and environmental conditions. The process of COPD is deteriorated by repeated episodes of exacerbations, which are the primary reason for COPD-related morbidity and mortality. Bacterial pathogens are commonly identified in patients’ respiratory tracts both in the stable state and during acute exacerbations, with significant changes in the prevalence of airway bacteria occurring during acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Therefore, the changes in microbial composition and host inflammatory responses will be necessary to investigate the mechanistic link between the airway microbiome and chronic pulmonary inflammation in COPD patients.MethodsWe performed metatranscriptomic and metagenomic sequencing on sputum samples for twelve AECOPD patients before treatment and for four of them stable COPD (stabilization of AECOPD patients after treatment). Sequencing reads were classified by Kraken2, and the host gene expression was analyzed by Hisat2 and HTseq. The correlation between genes was obtained by the Spearman correlation coefficient. Mann–Whitney U-test was applied to identify microbes that exhibit significantly different distribution in two groups.ResultsAt the phyla level, the top 5 dominant phyla were Firmicutes, Actinobacteria, Proteobacteria, Bacteroidetes, and Fusobacteria. The proportion of dominant gates in metagenomic data was similar in metatranscriptomic data. There were significant differences in the abundance of specific microorganisms at the class level between the two methods. No significant difference between AECOPD and stable COPD was found. However, the different expression levels of 5 host genes were significantly increased in stable COPD and were involved in immune response and inflammatory pathways, which were associated with macrophages.ConclusionOur study may provide a clue to investigate the mechanism of COPD and potential biomarkers in clinical diagnosis and treatment.

Medicinal Foods, YT and RH Combination, Suppress Cigarette Smoke-Induced Inflammation and Oxidative Stress by Inhibiting NF-κB/ERK Signaling Pathways.

Background Cigarette smoke is a risk factor for Chronic Obstructive Pulmonary Disease (COPD). Given the lack of COPD curative treatment, dietary management for COPD patients has become important. This study investigated whether the medicinal foods (YT and RH) could suppress cigarette smoke exposure-induced inflammation and oxidative stress. Methods Chronic pulmonary inflammation in male C57 mice was induced by a 4-week exposure to cigarette smoke (CS). The medicinal foods YT and RH were orally administered 1 week prior to CS exposure. The protective effects were assessed by measuring the pulmonary function and histopathological evaluations. Inflammatory cell numbers and cytokines levels in BALF and blood serum were analyzed by enzyme-linked immunosorbent assay (ELISA). Malondialdehyde (MDA) and superoxide dismutase (SOD) levels of the lung were analyzed. Furthermore, the levels of phosphorylated ERK and NF-κB in both the mice lungs and RAW264.7 cells were also detected. Results YT and RH combination (YT + RH) significantly improved pulmonary function and suppressed the inflammation, including cell number and cytokines in BALF relative to the CS group; histological examination revealed protective effects of YT + RH in the lungs of mice exposed to CS. Moreover, the MDA level in the lung of the YT + RH group of mice was lower, the SOD activity was higher, and in vitro treatment of YT and RH combination attenuated reactive oxygen species (ROS) expression in mouse macrophage RAW264.7 cells stimulated with cigarette smoke (CSE). YT + RH combination significantly reduced the expression of pNF-κB and pERK in the lung tissues and macrophage stimulated with CSE. Conclusions YT and RH combination attenuates cigarette smoke-induced inflammation and oxidative stress through inhibition of the NF-κB/ERK signaling pathway.

Dietary Docosahexaenoic Acid as a Potential Treatment for Semi-acute and Chronic Particle-Induced Pulmonary Inflammation in Balb/c Mice.

Acute and chronic inflammation are vital contributing factors to pulmonary diseases which can be triggered by exposure to occupational and man-made particles; however, there are no established treatments. One potential treatment shown to have anti-inflammatory capabilities is the dietary supplement docosahexaenoic acid (DHA), an omega-3 polyunsaturated fatty acid found in fish oil. DHA's anti-inflammatory mechanisms are unclear for particle-induced inflammation; therefore, this study evaluated DHA as a prophylactic treatment for semi-acute and chronic particle-induced inflammation in vivo. Balb/c mice were fed a control or 1% DHA diet and exposed to dispersion media, an inflammatory multi-walled carbon nanotube (MWCNT), or crystalline silica (SiO2) either once (semi-acute) or once a week for 4weeks (chronic). The hypothesis was that DHA will decrease pulmonary inflammatory markers in response to particle-induced inflammation. Results indicated that DHA had a trending anti-inflammatory effect in mice exposed to MWCNT. There was a general decrease in inflammatory signals within the lung lavage fluid and upregulation of M2c macrophage gene expression in the spleen tissue. In contrast, mice exposed to SiO2 while on the DHA diet significantly increased most inflammatory markers. However, DHA stabilized the phagolysosomal membrane upon prolonged treatment. This indicated that DHA treatment may depend upon certain inflammatory particle exposures as well as the length of the exposure.

SHP2: The protein tyrosine phosphatase involved in chronic pulmonary inflammation and fibrosis.

Chronic respiratory diseases (CRDs), including pulmonary fibrosis, chronic obstructive pulmonary disease (COPD), lung cancer, and asthma, are significant global health problems due to their prevalence and rising incidence. The roles of protein tyrosine kinases (PTKs) and protein tyrosine phosphatases (PTPs) in controlling tyrosine phosphorylation of targeting proteins modulate multiple physiological cellular responses and contribute to the pathogenesis of CRDs. Src homology-2 domain-containing PTP2 (SHP2) plays a pivotal role in modulating downstream growth factor receptor signaling and cytoplasmic PTKs, including MAPK/ERK, PI3K/AKT, and JAK/STAT pathways, to regulate cell survival and proliferation. In addition, SHP2 mutation and activation are commonly implicated in tumorigenesis. However, little is known about SHP2 in chronic pulmonary inflammation and fibrosis. This review discusses the potential involvement of SHP2 deregulation in chronic pulmonary inflammation and fibrosis, as well as the therapeutic effects of targeting SHP2 in CRDs.

Early-onset pulmonary and cutaneous vasculitis driven by constitutively active SRC-family kinase HCK

Inborn errors of immunity are genetic disorders characterized by various degrees of immune dysregulation that can manifest as immune deficiency, autoimmunity, or autoinflammation. The routine use of next-generation sequencing in the clinic has facilitated the identification of an ever-increasing number of inborn errors of immunity, revealing the roles of immunologically important genes in human pathologies. However, despite this progress, treatment is still extremely challenging. We sought to report a new monogenic autoinflammatory disorder caused by a de novo activating mutation, p.Tyr515∗, in hematopoietic cell kinase (HCK). The disease is characterized by cutaneous vasculitis and chronic pulmonary inflammation that progresses to fibrosis. Whole-exome sequencing, Sanger sequencing, mass spectrometry, and western blotting were performed to identify and characterize the pathogenic HCK mutation. Dysregulation of mutant HCK was confirmed exvivo in primary cells and invitro in transduced cell lines. Mutant HCK lacking the C-terminal inhibitory tyrosine Tyr522 exhibited increased kinase activity and enhanced myeloid cell priming, migration and effector functions, such as production of the inflammatory cytokines IL-1β, IL-6, IL-8, and TNF-α, and production of reactive oxygen species. These aberrant functions were reflected by inflammatory leukocyte infiltration of the lungs and skin. Moreover, an overview of the clinical course of the disease, including therapies, provides evidence for the therapeutic efficacy of the Janus kinase 1/2 inhibitor ruxolitinib in inflammatory lung disease. We propose HCK-driven pulmonary and cutaneous vasculitis as a novel autoinflammatory disorder of inborn errors of immunity.

Cigarette smoke extract combined with LPS down-regulates the expression of MRP2 in chronic pulmonary inflammation may be related to FXR

The transporter multidrug resistance protein 2 (MRP2) plays an important role in chronic pulmonary inflammation by transporting cigarette smoke and other related inflammatory mediators. However, it is not completely clear whether pulmonary inflammation caused by cigarette smoke extract (CSE) and lipopolysaccharide (LPS) is related to MRP2 and its signal factors. In this study, CSE combined with LPS was used to establish an inflammation model in vivo and in vitro. We found that compared with the control group, after CSE combined with LPS treatment, the expression of MRP2 in rat lung tissue in vivo and human alveolar cell line in vitro was down-regulated, while the expression of inflammatory factors was up-regulated. Through silencing and overexpression of FXR, it was found that silent FXR could down-regulate MRP2 and up-regulate the expression of inflammatory factors. On the contrary, overexpression of FXR could up-regulate MRP2 and down-regulate the expression of inflammatory factors. Our results show that CSE combined with LPS can down-regulate the expression of MRP2 under inflammatory conditions, and the down-regulation of MRP2 expression may be achieved partly through the FXR signal pathway.

Angiotensin-(1-7)/Mas receptor modulates anti-inflammatory effects of exercise training in a model of chronic allergic lung inflammation

AimsExercise training increases circulating and tissue levels of angiotensin-(1-7) [Ang-(1-7)], which was shown to attenuate inflammation and fibrosis in different diseases. Here, we evaluated whether Ang-(1-7)/Mas receptor is involved in the beneficial effects of aerobic training in a chronic model of asthma. Material and methodsBALB/c mice were subjected to a protocol of asthma induced by ovalbumin sensitization (OVA; 4 i.p. injections) and OVA challenge (3 times/week for 4 weeks). Simultaneously to the challenge period, part of the animals was continuously treated with Mas receptor antagonist (A779, 1 μg/h; for 28 days) and trained in a treadmill (TRE; 60% of the maximal capacity, 1 h/day, 5 days/week during 4 weeks). PGC1-α mRNA expression (qRT-PCR), plasma IgE and lung cytokines (ELISA), inflammatory cells infiltration (enzymatic activity assay) and airway remodeling (by histology) were evaluated. Key findingsBlocking the Mas receptor with A779 increased IgE and IL-13 levels and prevented the reduction in extracellular matrix deposition in airways in OVA-TRE mice. Mas receptor blockade prevented the reduction of myeloperoxidase activity, as well as, prevented exercise-induced IL-10 increase. These data show that activation of Ang-(1-7)/Mas receptor pathway is involved in the anti-inflammatory and anti-fibrotic effects of aerobic training in an experimental model of chronic asthma. SignificanceOur results support exercise training as a non-pharmacological tool to defeat lung remodeling induced by chronic pulmonary inflammation. Further, our result also supports development of new therapy based on Ang-(1-7) or Mas agonists as important tool for asthma treatment in those patients that cannot perform aerobic training.

Pneumoconiosis: current status and future prospects.

Pneumoconiosis refers to a spectrum of pulmonary diseases caused by inhalation of mineral dust, usually as the result of certain occupations. The main pathological features include chronic pulmonary inflammation and progressive pulmonary fibrosis, which can eventually lead to death caused by respiratory and/or heart failure. Pneumoconiosis is widespread globally, seriously threatening global public health. Its high incidence and mortality lie in improper occupational protection, and in the lack of early diagnostic methods and effective treatments. This article reviews the epidemiology, safeguard procedures, diagnosis, and treatment of pneumoconiosis, and summarizes recent research advances and future research prospects.

Blood eosinophil count in patients with COPD on inhaled corticosteroids in comparison with healthy smoker and nonsmoker controls

Background Chronic obstructive pulmonary disease (COPD) is associated with acute and chronic pulmonary inflammation in the lung and as a systemic inflammation. The blood eosinophil counts are now recommended by the Global Initiative for the Management of Obstructive Lung Disease as a guide of inhaled corticosteroid use in clinical practice, as it can predict its effect on the rate of COPD exacerbation. The increasing peripheral blood eosinophilic count in patients with COPD could explain the systemic eosinophilia in COPD, which causes increased lung eosinophil count in these patients, especially those on inhaled corticosteroids (ICS). Patients and methods The study included 56 patients with COPD who were active smokers with pack-years beyond 10 as cases. The control group includes 60 patients as healthy nonsmokers (HNS) and 66 patients as healthy current smokers (HS), with pack-year beyond 10. Prebronchodilator and postbronchodilator spirometry was done in the pulmonary function unit of the Chest Department, Ain Shams University Hospital, to confirm or to exclude the COPD diagnosis. The COPD cases were categorized as per the Global Initiative for the Management of Obstructive Lung Disease severity assessment guideline and were receiving budesonide 800 μg/day and formoterol 24 μg/day or salmeterol 100 μg and fluticasone propionate 500 μg twice daily. Skin prick test and complete blood count for its differential and eosinophil count were done for all cases. Results The study included 56 patients with COPD who were active smokers and received ICS. The control group included 60 patients as HNS along with 66 patients as healthy current smokers. The HNS group showed the least total leukocytic count of 5588.33±1081.13/µl and the least eosinophilic count of 99.47±91.51/µl, whereas the COPD group showed the highest total leukocytic count. A statistically significant relation was found also between COPD patients’ eosinophil count and the use of ICS, with P value 0.000. Conclusion The peripheral blood eosinophil counts collected from patients with COPD on ICS are significantly higher than the patients with COPD who are not using ICS and the healthy smoker and nonsmoker control group.

Evaluation of inflammatory miRNA155 and 146a expression in heart tissue of ovalbumin-sensitized male rats

Introduction: Asthma is a chronic pulmonary inflammation occurred in response to different allergens, leading to respiratory system insufficiency. The production of different inflammatory factors and enhanced immune system response may affect the function of other organs. The aim of this study was to investigate the expression of inflammatory microRNAs in cardiac tissue in asthmatic rat model. Methods: In this study, the animals were allocated into Control and Asthmatic rats (n=8). To induce asthma, rats were challenged with ovalbumin. 14 days after induction of asthma, rats were euthanized and Hematoxylin-Eosin staining was performed to assess pathological changes in pulmonary tissue. Serum levels of cardiac enzymes were measured using ELISA kits. Finally, transcription level of inflammatory miRNAs, miRNA-146a and -155, were measured using real-time PCR analysis. Results: Based on our findings, histological examination indicated the existence of pathological changes in pulmonary tissue after asthma induction. Bright-field analysis revealed an existence of inflammatory response and cytotoxicity in cardiac tissue. Also, the serum levels of CpK-MB, ALT, and AST were significantly higher in the serum of asthmatic group compared to control group (p<0.05). Finally, asthmatic condition induced the expression of (2-fold) miRNA-146a and (1.5-fold)-155 in cardiac tissue, respectively. Conclusion: As a conclusion, it could be concluded that asthmatic condition induces systemic inflammation in cardiac tissue. On a more general note, we propose that therapeutical approaches directed to inflammatory pathway may be required to preserve cardiac injuries caused of asthma.

Small Molecule CCR4 Antagonists Protect Mice from Aspergillus Infection and Allergy.

The ability to regulate the recruitment of immune cells makes chemokines and their receptors attractive drug targets in many inflammatory diseases. Based on its preferential expression on T helper type 2 (Th2) cells, C-C chemokine receptor type 4 (CCR4) has been widely studied in the context of allergic diseases, but recent evidence on the expression of CCR4 in other cell types has considerably expanded the potential applications of CCR4 antagonism. However, the current number of approved indications, as well as the portfolio of CCR4-targeting drugs, are still limited. In the present study, we have assessed the potential therapeutic efficacy of a CCR4 small molecule antagonist, SP50, discovered via an in silico-based approach, against a variety of pre-clinical settings of infection with the fungus Aspergillus fumigatus. We show that SP50 efficiently worked as prophylactic vaccine adjuvant in immunocompetent mice, protected against invasive aspergillosis in immunosuppressed mice. Further, the CCR4 antagonist prevented allergic bronchopulmonary aspergillosis in susceptible mice, and in a murine model of cystic fibrosis, a genetic disorder characterized by chronic pulmonary inflammation and recurrent infections. In conclusion, our results extend the potential applications of CCR4 antagonism and prompt for the development of novel compounds with the potential to progress to clinical trials.

Therapeutic treatment of dietary docosahexaenoic acid for particle-induced pulmonary inflammation in Balb/c mice.

The omega-3 polyunsaturated fatty acid docosahexaenoic acid (DHA) has been reported to suppress inflammation. Pulmonary inflammation can be directly linked to exposure of various occupational and man-made particles leading to pulmonary diseases. Therapeutic treatments are lacking for particle-induced pulmonary inflammation. These studies evaluated DHA as a therapeutic treatment for semi-acute and chronic particle-induced pulmonary inflammation. Balb/c mice were oropharyngeal instilled with hydrophobic multi-walled carbon nanotube (MWCNT) or hydrophilic crystalline silica (SiO2) either as one instillation (semi-acute) or once a week for 4weeks (chronic). One week later, the mice were placed on either a control or 1% DHA-containing diet for 3weeks (semi-acute) or 12weeks (chronic). Mice were assessed for inflammatory signaling within the lung lavage fluid, impact on phagolysosomal membrane permeability, shifts of macrophage phenotype gene expression (M1, M2a, M2b, and M2c), and pulmonary histopathology. DHA increased pulmonary inflammatory markers and lung pathology when mice were exposed to SiO2. There were trending decreases of inflammatory markers for MWCNT-exposed mice with DHA treatment, however, mostly not statistically significant. The anti-inflammatory benefits of DHA treatment depend upon the type of inflammatory particle, magnitude of inflammation, and duration of treatment.

The Japanese Herbal (Kampo) Medicine Hochuekkito Attenuates Lung Inflammation in Lung Emphysema.

Chronic obstructive pulmonary disease (COPD) is a systemic inflammatory disorder. It often causes weight loss, which is considered a poor prognostic factor. A Japanese herbal Kampo medicine, Hochuekkito (TJ-41), has been reported to prevent systemic inflammation and weight loss in COPD patients, but the underlying biological mechanisms remain unknown. In the present study, we investigated the role of TJ-41 in vivo using a mouse model of lung emphysema. We used lung epithelium-specific Taz conditional knockout mice (Taz CKO mice) as the lung emphysema model mimicking the chronic pulmonary inflammation in COPD. Acute inflammation was induced by intratracheal lipopolysaccharide administration, simulating COPD exacerbation. Mice were fed a diet containing 2% TJ-41 or a control diet. Taz CKO mice showed increased numbers of inflammatory cells in the bronchoalveolar lavage fluid compared to control mice. This effect was reduced by TJ-41 treatment. In the acute exacerbation model, TJ-41 mitigated the increased numbers of inflammatory cells in the bronchoalveolar lavage fluid and attenuated lung inflammation in histopathological studies. Additional in vitro experiments using the human macrophage cell line U-937 demonstrated that lipopolysaccharide-induced tumor necrosis factor-alpha expression was significantly downregulated by TJ-41. These results suggest that TJ-41 has anti-inflammatory effects in lung emphysema both in the chronic phase and during an acute exacerbation. In conclusion, our study sheds light on the anti-inflammatory effects of TJ-41 in lung emphysema. This establishes its potential as a new anti-inflammatory therapy and a preventive medicine for exacerbations during the long-time maintenance of COPD patients.

Impact of Combined Chronic Obstructive Pulmonary Disease Status and Systemic Inflammation on Outcome of Advanced NSCLC: Multicenter Retrospective Cohort Study.

BackgroundIn patients with non-small cell lung cancer (NSCLC), both chronic obstructive pulmonary disease (COPD) and systemic inflammatory biomarkers, such as neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR), have significant association with prognosis. NLR and PLR also predict mortality in patients with COPD alone. A combination of the two parameters may be helpful in a more individualized approach for predicting prognosis in NSCLC.MethodsMedical records of patients with stage IIIB and IV NSCLC from January 2012 to January 2018 in seven university hospitals were reviewed. Patients were categorized into four subgroups based on pulmonary function test results and cutoffs for NLR or PLR.ResultsA total of 277 patients were evaluated and categorized into non-COPD and COPD groups; 194 patients were in the non-COPD group and 83 patients were in the COPD group. The non-COPD group showed significantly longer overall survival (OS) compared with the COPD group (P = 0.019). Median survival was significantly different between high/low PLR groups (P < 0.001), between high/low NLR groups (P = 0.001), and between high/low c-reactive protein (CRP) groups (P < 0.001). PLR, NLR and CRP showed significant correlations with each other. PLR showed a significant negative linear correlation with FVC (absolute) (r = −0.149, P = 0.015), FVC (%) (r = −0.192, P = 0.002), DLCO (absolute) (r = −0.271, P < 0.001), DLCO (%) (r = −0.139, P = 0.032), and NLR (r = 0.718, P < 0.001). In the multivariate analysis, the high PLR, COPD sub-group showed significantly higher risk for mortality (HR 2.066 (1.175–3.633), P = 0.012) compared with the low-PLR non-COPD group. However, COPD-NLR subtype was not an independent predictor for OS.ConclusionA combination of COPD status and PLR may be a cost-effective and readily available prognostic marker in patients with advanced NSCLC.

Proinflammatory effects of environmental cadmium boost resistance to opportunistic pathogen Aspergillus fumigatus: Implications for sustained low-level pulmonary inflammation?

Cadmium (Cd) is one of the most toxic environmental heavy metals to which the general population is exposed mainly via the oral route. Owing to its immunomodulatory potential, orally acquired Cd affects antimicrobial immune defense in several organs, including the lungs. While there are data concerning Cd and viral and bacterial pulmonary infections, effects on fungal infections are not studied yet. In the present study, the effect of the Cd (5 mg/L for 30 days, in drinking water, the average daily Cd intake 0.641 ± 0.089 mg/kg) on the immune response of rats to pulmonary A. fumigatus infection was examined. Data obtained showed that orally acquired cadmium does not affect the elimination of the fungus in immunocompetent rats owing to the preservation of some aspects of innate immune responses (lung leukocyte infiltration and NBT reduction) and an increase in other (increased numbers of mucus-producing goblet cells, MPO release). Cd does not affect an IFN-γ response in lung leukocytes during the infection (despite suppression of cytokine production in cells of lung-draining lymph nodes), while it stimulates IL-17 and suppresses IL-10 response to the fungus. As a result, the elimination of the fungus occurs in a milieu with the prevailing proinflammatory response in Cd-exposed animals that preserved fungal elimination from the lungs, though with more intense injury to the lung tissue. Therefore, the proinflammatory microenvironment in the lungs created by Cd that sustains inflammatory/immune response to the fungus to which humans are exposed for a lifetime, raises a concern of orally acquired Cd as a risk factor for the development of chronic low-grade pulmonary inflammation.

CCR2 Mediates Chronic LPS-Induced Pulmonary Inflammation and Hypoalveolarization in a Murine Model of Bronchopulmonary Dysplasia.

The histopathology of bronchopulmonary dysplasia (BPD) includes hypoalveolarization and interstitial thickening due to abnormal myofibroblast accumulation. Chorioamnionitis and sepsis are major risk factors for BPD development. The cellular mechanisms leading to these lung structural abnormalities are poorly understood. We used an animal model with repeated lipopolysaccharide (LPS) administration into the airways of immature mice to simulate prolonged airway exposure to gram-negative bacteria, focusing on the role of C-C chemokine receptor type 2-positive (CCR2+) exudative macrophages (ExMf). Repetitive LPS exposure of immature mice induced persistent hypoalveolarization observed at 4 and 18 days after the last LPS administration. LPS upregulated the expression of lung pro-inflammatory cytokines (TNF-α, IL-17a, IL-6, IL-1β) and chemokines (CCL2, CCL7, CXCL1, and CXCL2), while the expression of genes involved in lung alveolar and mesenchymal cell development (PDGFR-α, FGF7, FGF10, and SPRY1) was decreased. LPS induced recruitment of ExMf, including CCR2+ ExMf, as well as other myeloid cells like DCs and neutrophils. Lungs of LPS-exposed CCR2−/− mice showed preserved alveolar structure and normal patterns of α-actin and PDGFRα expression at the tips of the secondary alveolar crests. Compared to wild type mice, a significantly lower number of ExMf, including TNF-α+ ExMf were recruited to the lungs of CCR2−/− mice following repetitive LPS exposure. Further, pharmacological inhibition of TLR4 with TAK-242 also blocked the effect of LPS on alveolarization, α-SMA and PDGFRα expression. TNF-α and IL-17a induced α-smooth muscle actin expression in the distal airspaces of E16 fetal mouse lung explants. In human preterm lung mesenchymal stromal cells, TNF-α reduced mRNA and protein expression of PDGFR-α and decreased mRNA expression of WNT2, FOXF2, and SPRY1. Collectively, our findings demonstrate that in immature mice repetitive LPS exposure, through TLR4 signaling increases lung inflammation and impairs lung alveolar growth in a CCR2-dependent manner.

Inducible Bronchus-Associated Lymphoid Tissue (iBALT) Attenuates Pulmonary Pathology in a Mouse Model of Allergic Airway Disease.

Inducible Bronchus Associated Lymphoid Tissue (iBALT) is an ectopic lymphoid tissue associated with severe forms of chronic lung diseases, including chronic obstructive pulmonary disease, rheumatoid lung disease, hypersensitivity pneumonitis and asthma, suggesting that iBALT may exacerbate these clinical conditions. However, despite the link between pulmonary pathology and iBALT formation, the role of iBALT in pathogenesis remains unknown. Here we tested whether the presence of iBALT in the lung prior to sensitization and challenge with a pulmonary allergen altered the biological outcome of disease. We found that the presence of iBALT did not exacerbate Th2 responses to pulmonary sensitization with ovalbumin. Instead, we found that mice with iBALT exhibited delayed Th2 accumulation in the lung, reduced eosinophil recruitment, reduced goblet cell hyperplasia and reduced mucus production. The presence of iBALT did not alter Th2 priming, but instead delayed the accumulation of Th2 cells in the lung following challenge and altered the spatial distribution of T cells in the lung. These results suggest that the formation of iBALT and sequestration of effector T cells in the context of chronic pulmonary inflammation may be a mechanism by which the immune system attenuates pulmonary inflammation and prevents excessive pathology.

Impaired mitochondrial function of alveolar macrophages in carbon nanotube-induced chronic pulmonary granulomatous disease

Human exposure to carbon nanotubes (CNT) has been associated with the development of pulmonary sarcoid-like granulomatous disease. Our previous studies demonstrated that multi-walled carbon nanotubes (MWCNT) induced chronic pulmonary granulomatous inflammation in mice. Granuloma formation was accompanied by decreased peroxisome proliferator-activated receptor gamma (PPARγ) and disrupted intracellular lipid homeostasis in alveolar macrophages. Others have shown that PPARγ activation increases mitochondrial fatty acid oxidation (FAO) to reduce free fatty acid accumulation. Hence, we hypothesized that the disrupted lipid metabolism suppresses mitochondrial FAO. To test our hypothesis, C57BL/6 J mice were instilled by an oropharyngeal route with 100 μg MWCNT freshly suspended in 35 % Infasurf. Control sham mice received vehicle alone. Sixty days following instillation, mitochondrial FAO was measured in permeabilized bronchoalveolar lavage (BAL) cells. MWCNT instillation reduced the mitochondrial oxygen consumption rate of BAL cells in the presence of palmitoyl-carnitine as mitochondrial fuel. MWCNT also reduced mRNA expression of mitochondrial genes regulating FAO, carnitine palmitoyl transferase-1 (CPT1), carnitine palmitoyl transferase-2 (CPT2), hydroxyacyl-CoA dehydrogenase subunit beta (HADHB), and PPARγ coactivator 1 alpha (PPARGC1A). Importantly, both oxidative stress and apoptosis in alveolar macrophages and lung tissues of MWCNT-instilled mice were increased. Because macrophage PPARγ expression has been reported to be controlled by miR-27b which is known to induce oxidative stress and apoptosis, we measured the expression of miR-27b. Results indicated elevated levels in alveolar macrophages from MWCNT-instilled mice compared to controls. Given that inhibition of FAO and apoptosis are linked to M1 and M2 macrophage activation, respectively, the expression of both M1 and M2 key indicator genes were measured. Interestingly, results showed that both M1 and M2 phenotypes of alveolar macrophages were activated in MWCNT-instilled mice. In conclusion, alveolar macrophages of MWCNT-instilled mice had increased miR-27b expression, which may reduce the expression of PPARγ resulting in attenuation of FAO. This reduction in FAO may lead to activation of M1 macrophages. The upregulation of miR-27b may also induce apoptosis, which in turn can cause M2 activation of alveolar macrophages. These observations indicate a possible role of miR-27b in impaired mitochondrial function in the chronic activation of alveolar macrophages by MWCNT and the development of chronic pulmonary granulomatous inflammation.