Endoplasmic Reticulum Stress and Unfolded Protein Response in Vernal Keratoconjunctivitis

Purpose

Vernal keratoconjunctivitis (VKC) is an ocular allergic disease characterized by a type 2 inflammation, tissue remodeling, and low quality of life for the affected patients. We investigated the involvement of endoplasmic reticulum (ER) stress and unfolded protein response in VKC.

Methods

Conjunctival imprints from VKC patients and normal subjects (CTs) were collected, and RNA was isolated, reverse transcribed, and analyzed with the Affymetrix microarray. Differentially expressed genes between VKC patients and CTs were evaluated. Genes related to ER stress, apoptosis, and autophagy were further considered. VKC and CT conjunctival biopsies were analyzed by immunohistochemistry (IHC) with specific antibodies against unfolded protein response (UPR), apoptosis, and inflammation. Conjunctival fibroblast and epithelial cell cultures were exposed to the conditioned medium of activated U937 monocytes and analyzed by quantitative PCR for the expression of UPR, apoptosis, autophagy, and inflammatory markers.

Results

ER chaperones HSPA5 (GRP78/BiP) and HYOU1 (GRP170) were upregulated in VKC patients compared to CTs. Genes encoding for ER transmembrane proteins, PKR-like ER kinase (PERK), activating transcription factor 6 (ATF6), ER-associated degradation (ERAD), and autophagy were upregulated, but not those related to apoptosis. Increased positive reactivity of BiP and ATF6 and unchanged expression of apoptosis markers were confirmed by IHC. Cell cultures in stress conditions showed an overexpression of UPR, proinflammatory, apoptosis, and autophagy markers.

Conclusions

A significant overexpression of genes encoding for ER stress, UPR, and pro-inflammatory pathway components was reported for VKC. Even though these pathways may lead to ER homeostasis, apoptosis, or inflammation, ER stress in VKC may predominantly contribute to promote inflammation.

Inhibition of Pro-Fibrotic Molecules Expression in Idiopathic Pulmonary Fibrosis-Derived Lung Fibroblasts by Lactose-Modified Hyaluronic Acid Compounds

Idiopathic pulmonary fibrosis (IPF) is a chronic inflammatory and fibrotic pathological condition with undefined effective therapies and a poor prognosis, partly due to the lack of specific and effective therapies. Galectin 3 (Gal-3), a pro-fibrotic ß-galactoside binding lectin, was upregulated in the early stages of the pathology, suggesting that it may be considered a marker of active fibrosis. In the present in vitro study, we use Hylach®, a lactose-modified hyaluronic acid able to bind Gal-3, to prevent the activation of lung myofibroblast and the consequent excessive ECM protein cell expression. Primary human pulmonary fibroblasts obtained from normal and IPF subjects activated with TGF-β were used, and changes in cell viability, fibrotic components, and pro-inflammatory mediator expression at both gene and protein levels were analyzed. Hylach compounds with a lactosylation degree of about 10% and 30% (Hylach1 and Hylach 2), administrated to TGF-β-stimulated lung fibroblast cultures, significantly downregulated α-smooth muscle actin (α-SMA) gene expression and decreased collagen type I, collagen type III, elastin, fibronectin gene and protein expression to near baseline values. This anti-fibrotic activity is accompanied by a strong anti-inflammatory effect and by a downregulation of the gene expression of Smad2 for both Hylachs in comparison to the native HA. In conclusion, the Gal-3 binding molecules Hylachs attenuated inflammation and TGF-β-induced over-expression of α-SMA and ECM protein expression by primary human lung fibroblasts, providing a new direction for the treatment of pulmonary fibrotic diseases.

Impaired autophagy in the lower airways and lung parenchyma in stable COPD

Background

There is increasing evidence of autophagy activation in COPD, but its role is complex and probably regulated through cell type-specific mechanisms. This study aims to investigate the autophagic process at multiple levels within the respiratory system, using different methods to clarify conflicting results reported so far.

Methods

This cross-sectional study was performed on bronchial biopsies and peripheral lung samples obtained from COPD patients (30 and 12 per sample type, respectively) and healthy controls (25 and 22 per sample type, respectively), divided by smoking history. Subjects were matched for age and smoking history. We analysed some of the most important proteins involved in autophagosome formation, such as LC3 and p62, as well as some molecules essential for lysosome function, such as lysosome-associated membrane protein 1 (LAMP1). Immunohistochemistry was used to assess the autophagic process in both sample types. ELISA and transcriptomic analysis were performed on lung samples.

Results

We found increased autophagic stimulus in smoking subjects, regardless of respiratory function. This was revealed by immunohistochemistry through a significant increase in LC3 (p<0.01) and LAMP1 (p<0.01) in small airway bronchiolar epithelium, alveolar septa and alveolar macrophages. Similar results were obtained in bronchial biopsy epithelium by evaluating LC3B (p<0.05), also increased in homogenate lung tissue using ELISA (p<0.05). Patients with COPD, unlike the others, showed an increase in p62 by ELISA (p<0.05). No differences were found in transcriptomics analysis.

Conclusions

Different techniques, applied at post-transcriptional level, confirm that cigarette smoke stimulates autophagy at multiple levels inside the respiratory system, and that autophagy failure may characterise COPD.

Bone Morphogenic Proteins and Their Antagonists in the Lower Airways of Stable COPD Patients

BACKGROUND

Bone morphogenic proteins (BMPs) and their antagonists are involved in the tissue development and homeostasis of various organs.

OBJECTIVE

To determine transcriptomic and protein expression of BMPs and their antagonists in stable COPD.

METHODS

We measured the expression and localization of BMPs and some relevant antagonists in bronchial biopsies of stable mild/moderate COPD (MCOPD) (n = 18), severe/very severe COPD (SCOPD) (n = 16), control smokers (CS) (n = 13), and control non-smokers (CNS) (n = 11), and in lung parenchyma of MCOPD (n = 9), CS (n = 11), and CNS (n = 9) using immunohistochemistry and transcriptome analysis, in vitro after the stimulation of the 16HBE cells.

RESULTS

In bronchial biopsies, BMP4 antagonists CRIM1 and chordin were increased in the bronchial epithelium and lamina propria of COPD patients. BMP4 expression was decreased in the bronchial epithelium of SCOPD and MCOPD compared to CNS. Lung transcriptomic data showed non-significant changes between groups. CRIM1 and chordin were significantly decreased in the alveolar macrophages and alveolar septa in COPD patients. External 16HBE treatment with BMP4 protein reduced the bronchial epithelial cell proliferation.

CONCLUSIONS

These data show an imbalance between BMP proteins and their antagonists in the lungs of stable COPD. This imbalance may play a role in the remodeling of the airways, altering the regenerative-reparative responses of the diseased bronchioles and lung parenchyma.

Phenotype overlap in the natural history of asthma

The heterogeneity of asthma makes it challenging to unravel the pathophysiologic mechanisms of the disease. Despite the wealth of research identifying diverse phenotypes, many gaps still remain in our knowledge of the disease's complexity. A crucial aspect is the impact of airborne factors over a lifetime, which often results in a complex overlap of phenotypes associated with type 2 (T2), non-T2 and mixed inflammation. Evidence now shows overlaps between the phenotypes associated with T2, non-T2 and mixed T2/non-T2 inflammation. These interconnections could be induced by different determinants such as recurrent infections, environmental factors, T-helper plasticity and comorbidities, collectively resulting in a complex network of distinct pathways generally considered as mutually exclusive. In this scenario, we need to abandon the concept of asthma as a disease characterised by distinct traits grouped into static segregated categories. It is now evident that there are multiple interplays between the various physiologic, cellular and molecular features of asthma, and the overlap of phenotypes cannot be ignored.

Bacterial load and related innate immune response in the bronchi of rapid decliners with chronic obstructive pulmonary disease

BACKGROUND

Characterization of COPD patients with rapid lung functional decline is of interest for prognostic and therapeutic reasons. We recently reported an impaired humoral immune response in rapid decliners.

OBJECTIVE

To determine the microbiota associated to markers of innate immune host response in COPD patients with rapid lung functional decline.

METHODS

In COPD patients monitored for at least 3 years (mean ± SD: 5.8 ± 3 years) for lung functional decline, the microbiota and related markers of immune response was measured in bronchial biopsies of patients with different lung functional decline (rate of FEV1% lung functional decline: no decline FEV1%, ≤20 ml/year n = 21, slow decline FEV1%, >20 ≤ 70 ml/year, n = 14 and rapid decline FEV1%, >70 ml/year, n = 15) using qPCR for microbiota and immunohistochemistry for cell-receptors and inflammatory markers.

MAIN RESULTS

Pseudomonas aeruginosa and Streptococcus pneumoniae were increased in rapid decliners vs slow decliners, S. pneumoniae was also increased compared to non decliners. In all patients, S. pneumoniae (copies/ml) positively correlated with pack-years consumption, lung function decline, TLR4, NOD1, NOD2 scored in bronchial epithelium and NOD1/mm² in lamina propria.

CONCLUSION

These data show an imbalance of microbiota components in rapid decliners which is associated to the expression of the related cell-receptors in all COPD patients. These findings may help in the prognostic stratification and treatment of patients.

The Anti-Inflammatory Effect of Lactose-Modified Hyaluronic Acid Molecules on Primary Bronchial Fibroblasts of Smokers

The progression of smoking-related diseases is characterized by macrophage-mediated inflammation, which is responsible for an increased expression of proinflammatory cytokines and galectins, molecules that bind specifically to β-galactoside sugars. This study aimed to assess the anti-inflammatory and antioxidant effects of a broad selection of differently lactose-modified hyaluronic acids (HA) named HYLACH^®, which are able to bind proinflammatory galectins. The best HYLACH ligands for Gal-3 were selected in silico and their activities were tested in vitro on primary human bronchial fibroblasts obtained from smokers and inflamed with the conditioned medium of activated U937 monocytes. Changes in cell viability, ROS generation, proinflammatory mediators, and MMP expression, at both gene and protein levels, were analyzed. The in silico results show that HYLACH with a percentage of lactosylation of 10-40% are the best ligands for Gal-3. The in vitro study revealed that HYLACH compounds with 10, 20, and 40% lactosylation (HYLACH-1-2-3) administrated to inflamed cell cultures counteracted the oxidative damage and restored gene and protein expression for IL-1β, TNF-α, IL-6, Gal-1, Gal-3, and MMP-3 to near baseline values. The evidence that HYLACH attenuated macrophage-induced inflammation, inhibited MMP expression, and exhibited antioxidative effects provide an initial step toward the development of a therapeutic treatment suitable for smoking-related diseases.

Decreased humoral immune response in the bronchi of rapid decliners with chronic obstructive pulmonary disease

Background

Identification of COPD patients with a rapid decline in FEV1 is of particular interest for prognostic and therapeutic reasons.

Objective

To determine the expression of markers of inflammation in COPD patients with rapid functional decline in comparison to slow or no decliners.

Methods

In COPD patients monitored for at least 3 years (mean ± SD: 5.8 ± 3 years) for lung functional decline, the expression and localization of inflammatory markers was measured in bronchial biopsies of patients with no lung functional decline (FEV1% + 30 ± 43 ml/year, n = 21), slow (FEV1% ml/year, − 40 ± 19, n = 14) and rapid decline (FEV1% ml/year, − 112 ± 53, n = 15) using immunohistochemistry. ELISA test was used for polymeric immunoglobulin receptor (pIgR) quantitation “in vitro”.

Results

The expression of secretory IgA was significantly reduced in bronchial epithelium (p = 0.011) and plasma cell numbers was significantly reduced in the bronchial lamina propria (p = 0.017) of rapid decliners compared to no decliners. Bronchial inflammatory cell infiltration, CD4, CD8, CD68, CD20, NK, neutrophils, eosinophils, mast cells, pIgR, was not changed in epithelium and lamina propria of rapid decliners compared to other groups. Plasma cells/mm² correlated positively with scored total IgA in lamina propria of all patients. “In vitro” stimulation of 16HBE cells with LPS (10 μg/ml) and IL-8 (10 ng/ml) induced a significant increase while H₂O₂ (100 μM) significantly decreased pIgR epithelial expression.

Conclusion

These data show an impaired humoral immune response in rapid decliners with COPD, marked by reduced epithelial secretory IgA and plasma cell numbers in the bronchial lamina propria. These findings may help in the prognostic stratification and treatment of COPD.

Predictors of Low and High Exhaled Nitric Oxide Values in Asthma: A Real-World Study

BACKGROUND

In asthma, exhaled nitric oxide (FENO) is a clinically established biomarker of airway T2 inflammation and an indicator for anti-inflammatory therapy.

OBJECTIVES

The aim of the study was to identify, in an observational real-world cross-sectional study, the main characteristics of patients with asthma as classified by their FENO level.

METHOD

We stratified 398 patients with stable mild-to-severe asthma according to FENO level as low (≤25 ppb) versus elevated (>25 ppb), subdividing the latter into two subgroups: moderately elevated (26-50 ppb) versus very high FENO (>50 ppb). Clinical, functional, and blood parameters were extrapolated from patients' chart data and compared with the FENO stratification. Predictors of low and elevated FENO asthma were detected by logistic regression model.

RESULTS

Low BMI, higher blood eosinophilia, allergen poly-sensitization, the severest airflow obstruction (FEV1/FVC), and anti-leukotriene use are predictors of elevated FENO values in asthma, as well as persistent rhinitis and chronic rhinosinusitis with or without nasal polyps. Beyond these, younger age, more than 2 asthma exacerbations/year, higher airflow reversibility (post-bronchodilator ∆FEV1), and oral corticosteroid dependence are predictors of very high FENO values. In contrast, obesity, obstructive sleep apnoea syndrome, gastroesophageal reflux disease, arterial hypertension, and myocardial infarction are predictors of low FENO asthma. In our population, FENO correlated with blood eosinophils, airflow obstruction, and reversibility and negatively correlated with age and BMI.

CONCLUSIONS

Stratifying patients by FENO level can identify specific asthma phenotypes with distinct clinical features and predictors useful in clinical practice to tailor treatment and improve asthmatic patients' outcomes.

Bacterial and viral infections and related inflammatory responses in chronic obstructive pulmonary disease

In chronic obstructive pulmonary disease (COPD) patients, bacterial and viral infections play a relevant role in worsening lung function and, therefore, favour disease progression. The inflammatory response to lung infections may become a specific indication of the bacterial and viral infections. We here review data on the bacterial-viral infections and related airways and lung parenchyma inflammation in stable and exacerbated COPD, focussing our attention on the prevalent molecular pathways in these different clinical conditions. The roles of macrophages, autophagy and NETosis are also briefly discussed in the context of lung infections in COPD. Controlling their combined response may restore a balanced lung homeostasis, reducing the risk of lung function decline. KEY MESSAGE Bacteria and viruses can influence the responses of the innate and adaptive immune system in the lung of chronic obstructive pulmonary disease (COPD) patients. The relationship between viruses and bacterial colonization, and the consequences of the imbalance of these components can modulate the inflammatory state of the COPD lung. The complex actions involving immune trigger cells, which activate innate and cell-mediated inflammatory responses, could be responsible for the clinical consequences of irreversible airflow limitation, lung remodelling and emphysema in COPD patients.

A microRNA-21-mediated SATB1/S100A9/NF-κB axis promotes chronic obstructive pulmonary disease pathogenesis

[Figure: see text].

Role of Atypical Chemokines and Chemokine Receptors Pathways in the Pathogenesis of COPD

Chronic obstructive pulmonary disease (COPD) represents a heightened inflammatory response in the lung generally resulting from tobacco smoking-induced recruitment and activation of inflammatory cells and/or activation of lower airway structural cells. Several mediators can modulate activation and recruitment of these cells, particularly those belonging to the chemokines (conventional and atypical) family. There is emerging evidence for complex roles of atypical chemokines and their receptors (such as high mobility group box 1 (HMGB1), antimicrobial peptides, receptor for advanced glycosylation end products (RAGE) or toll-like receptors (TLRs)) in the pathogenesis of COPD, both in the stable disease and during exacerbations. Modulators of these pathways represent potential novel therapies for COPD and many are now in preclinical development. Inhibition of only a single atypical chemokine or receptor may not block inflammatory processes because there is redundancy in this network. However, there are many animal studies that encourage studies for modulating the atypical chemokine network in COPD. Thus, few pharmaceutical companies maintain a significant interest in developing agents that target these molecules as potential antiinflammatory drugs. Antibody-based (biological) and small molecule drug (SMD)-based therapies targeting atypical chemokines and/or their receptors are mostly at the preclinical stage and their progression to clinical trials is eagerly awaited. These agents will most likely enhance our knowledge about the role of atypical chemokines in COPD pathophysiology and thereby improve COPD management.

Oxidative and Nitrosative Stress in the Pathogenesis of Obstructive Lung Diseases of Increasing Severity

The imbalance between increased oxidative agents and antioxidant defence mechanisms is central in the pathogenesis of obstructive lung diseases such as asthma and COPD. In these patients, there are increased levels of reactive oxygen species. Superoxide anions (O₂ -), Hydrogen Peroxide (H₂O₂) and hydroxyl radicals (•OH) are critical for the formation of further cytotoxic radicals in the bronchi and lung parenchyma. Chronic inflammation, partly induced by oxidative stress, can further increase the oxidant burden through activated phagocytic cells (neutrophils, eosinophils, macrophages), particularly in severer disease states. Antioxidants and anti-inflammatory genes are, in fact, frequently downregulated in diseased patients. Nrf2, which activates the Antioxidant Response Element (ARE) leading to upregulation of GPx, thiol metabolism-associated detoxifying enzymes (GSTs) and stressresponse genes (HO-1) are all downregulated in animal models and patients with asthma and COPD. An exaggerated production of Nitric Oxide (NO) in the presence of oxidative stress can promote the formation of oxidizing reactive nitrogen species, such as peroxynitrite (ONO₂ -), leading to nitration and DNA damage, inhibition of mitochondrial respiration, protein dysfunction, and cell damage in the biological systems. Protein nitration also occurs by activation of myeloperoxidase and H₂O₂, promoting oxidation of nitrite (NO₂ -). There is increased nitrotyrosine and myeloperoxidase in the bronchi of COPD patients, particularly in severe disease. The decreased peroxynitrite inhibitory activity found in induced sputum of COPD patients correlates with pulmonary function. Markers of protein nitration - 3- nitrotyrosine, 3-bromotyrosine, and 3-chlorotyrosine - are increased in the bronchoalveolar lavage of severe asthmatics. Targeting the oxidative, nitrosative stress and associated lung inflammation through the use of either denitration mechanisms or new drug delivery strategies for antioxidant administration could improve the treatment of these chronic disabling obstructive lung diseases.

Impact of Galectin-3 Circulating Levels on Frailty in Elderly Patients with Systolic Heart Failure

Background: Heart Failure (HF), a leading cause of morbidity and mortality, represents a relevant trigger for the development of frailty in the elderly. Inflammation has been reported to play an important role in HF and frailty pathophysiology. Galectin-3 (Gal-3), whose levels increase with aging, exerts a relevant activity in the processes of cardiac inflammation and fibrosis. The aim of the present study was to investigate the potential of Galectin-3 to serve as a biomarker of frailty in HF patients. Methods: 128 consecutive patients aged 65 and older with the diagnosis of systolic HF underwent a frailty assessment and blood sample collection for serum Gal-3 detection. A multivariable regression analysis and decision curve analysis (DCA) were used to identify significant predictors of frailty. Results: Frailty was present in 42.2% of patients. Age: Odds Ratio (OR) = 3.29; 95% Confidence Interval CI (CI) = 1.03-10.55, Cumulative Illness Rating Scale Comorbidity Index (CIRS-CI): OR = 1.85; 95% CI = 1.03-3.32, C-Reactive phase Protein (CRP) OR = 3.73; 95% CI = 1.24-11.22, N-terminal-pro-Brain Natriuretic Peptide (NT-proBNP): OR = 2.39; 95% CI = 1.21-4.72 and Gal-3: OR = 5.64; 95% CI = 1.97-16.22 resulted in being significantly and independently associated with frailty. The DCA demonstrated that the addition of Gal-3 in the prognostic model resulted in an improved clinical 'net' benefit. Conclusions: Circulating levels of Gal-3 are independently associated with frailty in elderly patients with systolic HF.

Clinical Characterization of the Frequent Exacerbator Phenotype in Asthma

Background: Asthma exacerbation is episodic worsening of respiratory symptoms in conjunction with the deterioration of lung function, which may occur independently from the asthma severity hampering asthmatics’ quality of life. This study aimed to characterize the patient phenotype more prone to asthma exacerbation (oral corticosteroid burst ≥2 per year) to allow the proper identification of such patients. Methods: This real-life, observational, cross-sectional study evaluated 464 asthmatic patients stratified according to the asthma exacerbations experienced in the previous year. Clinical, functional, and blood parameters were retrieved from chart data and were representative of patients in stable conditions. Results: The frequent asthma exacerbator was more commonly female, suffered from chronic rhinosinusitis with nasal polyposis, had reduced lung function and peripheral oxygen saturation, and had increased daily activity limitations. These patients often had severe asthma and more frequently needed hospitalization in their lives. Furthermore, the frequent asthma exacerbator had higher concentrations of serum immunoglobulin E (IgE) and exhaled nitric oxide with cut-off risk values of 107.5 kU/L (OR = 4.1) and 43.35 ppb (OR = 3.8), respectively. Conclusions: This study illustrates the clinical features of the frequent asthma exacerbator phenotype. Nevertheless, serum IgE and exhaled nitric oxide could allow the identification of this phenotype and the establishment of an appropriate therapeutic approach.

Evaluation of Innate Immune Mediators Related to Respiratory Viruses in the Lung of Stable COPD Patients

Background: Little is known about the innate immune response to viral infections in stable Chronic Obstructive Pulmonary Disease (COPD). Objectives: To evaluate the innate immune mediators related to respiratory viruses in the bronchial biopsies and lung parenchyma of stable COPD patients. Methods: We evaluated the immunohistochemical (IHC) expression of Toll-like receptors 3-7-8-9 (TLR-3-7-8-9), TIR domain-containing adaptor inducing IFNβ (TRIF), Interferon regulatory factor 3 (IRF3), Phospho interferon regulatory factor 3 (pIRF3), Interferon regulatory factor 7 (IRF7), Phospho interferon regulatory factor 7 (pIRF7), retinoic acid-inducible gene I (RIG1), melanoma differentiation-associated protein 5 (MDA5), Probable ATP-dependent RNA helicase DHX58 (LGP2), Mitochondrial antiviral-signaling protein (MAVS), Stimulator of interferon genes (STING), DNA-dependent activator of IFN regulatory factors (DAI), forkhead box protein A3(FOXA3), Interferon alfa (IFNα), and Interferon beta (IFNβ) in the bronchial mucosa of patients with mild/moderate (n = 16), severe/very severe (n = 1618) stable COPD, control smokers (CS) (n = 1612), and control non-smokers (CNS) (n = 1612). We performed similar IHC analyses in peripheral lung from COPD (n = 1612) and CS (n = 1612). IFNα and IFNβ were assessed in bronchoalveolar lavage (BAL) supernatant from CNS (n = 168), CS (n = 169) and mild/moderate COPD (n = 1612). Viral load, including adenovirus-B, -C, Bocavirus, Respiratory syncytial Virus (RSV), Human Rhinovirus (HRV), Coronavirus, Influenza virus A (FLU-A), Influenza virus B (FLU-B), and Parainfluenzae-1 were measured in bronchial rings and lung parenchyma of COPD patients and the related control group (CS). Results: Among the viral-related innate immune mediators, RIG1, LGP2, MAVS, STING, and DAI resulted well expressed in the bronchial and lung tissues of COPD patients, although not in a significantly different mode from control groups. Compared to CS, COPD patients showed no significant differences of viral load in bronchial rings and lung parenchyma. Conclusions: Some virus-related molecules are well-expressed in the lung tissue and bronchi of stable COPD patients independently of the disease severity, suggesting a “primed” tissue environment capable of sensing the potential viral infections occurring in these patients.

Role of the mucins in pathogenesis of COPD: implications for therapy

Introduction: Evidence accumulated in the last decade has started to reveal the enormous complexity in the expression, interactions and functions of the large number of different mucins present in the different compartments of the human lower airways. This occurs both in normal subjects and in COPD patients in different clinical phases and stages of severity.Areas covered: We review the known physiological mechanisms that regulate mucin production in human lower airways of normal subjects, the changes in mucin synthesis/secretion in COPD patients and the clinical efficacy of drugs that modulate mucin synthesis/secretion.Expert opinion: It is evident that the old simplistic concept that mucus hypersecretion in COPD patients is associated with negative clinical outcomes is not valid and that the therapeutic potential of 'mucolytic drugs' is under-appreciated due to the complexity of the associated molecular network(s). Likewise, our current knowledge of the effects of the drugs already available on the market that target mucin synthesis/secretion/structure in the lower airways is extremely limited and often indirect and more well-controlled clinical trials are needed in this area.

Elevated serum IgE, oral corticosteroid dependence and IL-17/22 expression in highly neutrophilic asthma

Information on the clinical traits associated with bronchial neutrophilia in asthma is scant, preventing its recognition and adequate treatment. We aimed to assess the clinical, functional and biological features of neutrophilic asthma and identify possible predictors of bronchial neutrophilia.The inflammatory phenotype of 70 mild-to-severe asthma patients was studied cross-sectionally based on the eosinophilic/neutrophilic counts in their bronchial lamina propria. Patients were classified as neutrophilic or non-neutrophilic. Neutrophilic asthma patients (neutrophil count cut-off: 47.17 neutrophils·mm-2; range: 47.17-198.11 neutrophils·mm-2; median: 94.34 neutrophils·mm-2) were further classified as high (≥94.34 neutrophils·mm-2) or intermediate (47.17- <94.34 neutrophils·mm-2). The effect of smoking ≥10 pack-years was also assessed.Neutrophilic asthma patients (n=38; 36 mixed eosinophilic/neutrophilic) had greater disease severity, functional residual capacity, inhaled corticosteroid (ICS) dose and exacerbations, and lower forced vital capacity (FVC) % pred and forced expiratory volume in 1 s (FEV1) reversibility than non-neutrophilic asthma patients (n=32; 28 eosinophilic and four paucigranulocytic). Neutrophilic asthma patients had similar eosinophil counts, increased bronchial CD8+, interleukin (IL)-17-F+ and IL-22+ cells, and decreased mast cells compared with non-neutrophilic asthma patients. FEV1 and FVC reversibility were independent predictors of bronchial neutrophilia in our cohort. High neutrophilic patients (n=21) had increased serum IgE levels, sensitivity to perennial allergens, exacerbation rate, oral corticosteroid dependence, and CD4+ and IL-17F+ cells in their bronchial mucosa. Excluding smokers revealed increased IL-17A+ and IL-22+ cells in highly neutrophilic patients.We provide new evidence linking the presence of high bronchial neutrophilia in asthma to an adaptive immune response associated with allergy (IgE) and IL-17/22 cytokine expression. High bronchial neutrophilia may discriminate a new endotype of asthma. Further research is warranted on the relationship between bronchoreversibility and bronchial neutrophilia.

Bacterial load and inflammatory response in sputum of alpha-1 antitrypsin deficiency patients with COPD

Background

Airway inflammation may drive the progression of chronic obstructive pulmonary disease (COPD) associated with alpha-1 antitrypsin deficiency (AATD), but the relationship between airway microbiota and inflammation has not been investigated.

Methods

We studied 21 non-treated AATD (AATD-noT) patients, 20 AATD-COPD patients under augmentation therapy (AATD-AT), 20 cigarette smoke-associated COPD patients, 20 control healthy smokers (CS) and 21 non-smokers (CON) with normal lung function. We quantified sputum inflammatory cells and inflammatory markers (IL-27, CCL3, CCL5, CXCL8, LTB₄, MPO) by ELISA, total bacterial load (16S) and pathogenic bacteria by qRT-PCR.

Results

AATD-AT patients were younger but had similar spirometric and DLCO values compared to cigarette smoke-associated COPD, despite a lower burden of smoking history. Compared to cigarette smoke-associated COPD, AATD-noT and AATD-AT patients had lower sputum neutrophil levels (p=0.0446, p=0.0135), total bacterial load (16S) (p=0.0081, p=0.0223), M. catarrhalis (p=0.0115, p=0.0127) and S. pneumoniae (p=0.0013, p=0.0001). Sputum IL-27 was significantly elevated in CS and cigarette smoke-associated COPD. AATD-AT, but not AATD-noT patients, had IL-27 sputum levels (pg/ml) significantly lower than COPD (p=0.0297) and these positively correlated with FEV₁% predicted values (r=0.578, p=0.0307).

Conclusions

Compared to cigarette smoke-associated COPD, AATD-AT (COPD) patients have a distinct airway inflammatory and microbiological profile. The decreased sputum bacterial load and IL-27 levels in AATD-AT patients suggests that augmentation therapy play a role in these changes.

Blood MCP-1 levels are increased in chronic obstructive pulmonary disease patients with prevalent emphysema

Background and aims

Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease characterized by different phenotypes with either bronchial airways alterations or emphysema prevailing. As blood biomarkers could be clinically useful for COPD stratification, we aimed at investigating the levels of blood biomarkers in COPD patients differentiated by phenotype: prevalent chronic airway disease versus emphysema.

Methods

In 23 COPD patients with prevalent airway disease (COPD-B), 22 COPD patients with prevalent emphysema (COPD-E), 9 control smokers (CSs), and 18 control nonsmokers (CNSs), we analyzed the expression levels of interleukin (IL)-1α, IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, tumor necrosis factor (TNF)-α, interferon (IFN)-γ, epidermal growth factor (EGF), monocyte chemotactic protein (MCP)-1, and vascular endothelial growth factor by enzyme-linked immunosorbent assay in plasma/serum; glutathione peroxidase and superoxide dismutase (SOD)-1 by immunochemical kits in plasma; and free F2-isoprostanes (F2-IsoPs) by gas chromatography in plasma.

Results

F2-IsoPs level was increased in COPD-B and COPD-E compared with CSs and CNSs; in addition, CS showed higher levels than CNSs; SOD1 level was lower in COPD-B and COPD-E than that in CNSs. Interestingly, MCP-1 level was higher only in COPD-E versus CSs and CNSs; EGF and IL-8 levels were higher in COPD-B and COPD-E versus CNSs; IL-6 level was increased in all three smoking groups (COPD-B, COPD-E, and CSs) versus CNS; IFN-γ and IL-1α levels were higher in CSs than in CNSs; and IL-1α level was also higher in CSs versus COPD-B and COPD-E. In all subjects, F2-IsoPs level correlated positively and significantly with MCP-1, IL-2, IL-1β, IFN-γ, and TNF-α and negatively with SOD1. When correlations were restricted to COPD-E and COPD-B groups, F2-IsoPs maintained the positive associations with IFN-γ, TNF-α, and IL-2.

Conclusion

We did not find any specific blood biomarkers that could differentiate COPD patients with prevalent airway disease from those with prevalent emphysema. The MCP-1 increase in COPD-E, associated with the imbalance of oxidant/antioxidant markers, may play a role in inducing emphysema.

TGF-β Signaling Pathways in Different Compartments of the Lower Airways of Patients With Stable COPD

BACKGROUND

The expression and localization of transforming growth factor-β (TGF-β) pathway proteins in different compartments of the lower airways of patients with stable COPD is unclear. We aimed to determine TGF-β pathway protein expression in patients with stable COPD.

METHODS

The expression and localization of TGF-β pathway components was measured in the bronchial mucosa and peripheral lungs of patients with stable COPD (n = 44), control smokers with normal lung function (n = 24), and control nonsmoking subjects (n = 11) using immunohistochemical analysis.

RESULTS

TGF-β1, TGF-β3, and connective tissue growth factor expression were significantly decreased in the bronchiolar epithelium, with TGF-β1 also decreased in alveolar macrophages, in patients with stable COPD compared with control smokers with normal lung function. TGF-β3 expression was increased in the bronchial lamina propria of both control smokers with normal lung function and smokers with mild/moderate stable COPD compared with control nonsmokers and correlated significantly with pack-years of smoking. However, TGF-β3⁺ cells decreased in patients with severe/very severe COPD compared with control smokers. Latent TGF-β binding protein 1 expression was increased in the bronchial lamina propria in subjects with stable COPD of all severities compared with control smokers with normal lung function. Bone morphogenetic protein and activin membrane-bound inhibitor expression (BAMBI) in the bronchial mucosa was significantly increased in patients with stable COPD of all severities compared with control subjects. No other significant differences were observed between groups for all the other molecules studied in the bronchial mucosa and peripheral lung.

CONCLUSIONS

Expression of TGF-βs and their regulatory proteins is distinct within different lower airway compartments in stable COPD. Selective reduction in TGF-β1 and enhanced BAMBI expression may be associated with the increase in autoimmunity in COPD.

HSP60 activity on human bronchial epithelial cells

HSP60 has been implicated in chronic inflammatory disease pathogenesis, including chronic obstructive pulmonary disease (COPD), but the mechanisms by which this chaperonin would act are poorly understood. A number of studies suggest a role for extracellular HSP60, since it can be secreted from cells and bind Toll-like receptors; however, the effects of this stimulation have never been extensively studied. We investigated the effects (pro- or anti-inflammatory) of HSP60 in human bronchial epithelial cells (16-HBE) alone and in comparison with oxidative, inflammatory, or bacterial challenges. 16-HBE cells were cultured for 1–4 h in the absence or presence of HSP60, H₂O₂, lipopolysaccharide (LPS), or cytomix. The cell response was evaluated by measuring the expression of IL-8 and IL-10, respectively, pro- and anti-inflammatory cytokines involved in COPD pathogenesis, as well as of pertinent TLR-4 pathway mediators. Stimulation with HSP60 up-regulated IL-8 at mRNA and protein levels and down-regulated IL-10 mRNA and protein. Likewise, CREB1 mRNA was up-regulated. H₂O₂ and LPS up-regulated IL-8. Experiments with an inhibitor for p38 showed that this mitogen-activated protein kinase could be involved in the HSP60-mediated pro-inflammatory effects. HSP60 showed pro-inflammatory properties in bronchial epithelial cells mediated by activation of TLR-4-related molecules. The results should prompt further studies on more complex ex-vivo or in-vivo models with the aim to elucidate further the role of those molecules in the pathogenesis of COPD.

Bronchial inflammation and bacterial load in stable COPD is associated with TLR4 overexpression

Toll-like receptors (TLRs) and nucleotide-binding oligomerisation domain (NOD)-like receptors (NLRs) are two major forms of innate immune sensors but their role in the immunopathology of stable chronic obstructive pulmonary disease (COPD) is incompletely studied. Our objective here was to investigate TLR and NLR signalling pathways in the bronchial mucosa in stable COPD.

Using immunohistochemistry, the expression levels of TLR2, TLR4, TLR9, NOD1, NOD2, CD14, myeloid differentiation primary response gene 88 (MyD88), Toll-interleukin-1 receptor domain-containing adaptor protein (TIRAP), and the interleukin-1 receptor-associated kinases phospho-IRAK1 and IRAK4 were measured in the bronchial mucosa of subjects with stable COPD of different severity (n=34), control smokers (n=12) and nonsmokers (n=12). The bronchial bacterial load of Pseudomonas aeruginosa, Haemophilus influenzae, Moraxella catarrhalis and Streptococcus pneumoniae was measured by quantitative real-time PCR.

TLR4 and NOD1 expression was increased in the bronchial mucosa of patients with severe/very severe stable COPD compared with control subjects. TLR4 bronchial epithelial expression correlated positively with CD4+ and CD8+ cells and airflow obstruction. NOD1 expression correlated with CD8+ cells. The bronchial load of P. aeruginosa was directly correlated, but H. influenzae inversely correlated, with the degree of airflow obstruction. Bacterial load did not correlate with inflammatory cells.

Bronchial epithelial overexpression of TLR4 and NOD1 in severe/very severe stable COPD, associated with increased bronchial inflammation and P. aeruginosa bacterial load, may play a role in the pathogenesis of COPD.

Identification of IL-17F/frequent exacerbator endotype in asthma

BACKGROUND

Severe asthma might be associated with overexpression of T_h17 cytokines, which induce neutrophil recruitment via neutrophil-mobilizing cytokines in airways.

OBJECTIVE

To study IL-17-related cytokines in nasal/bronchial biopsies from controls and mild asthmatics (MAs) to severe asthmatics (SAs) in relation to exacerbation rate.

METHODS

Inflammatory cells and IL-17A⁺, IL-17F⁺, IL-21⁺, IL-22⁺, and IL-23⁺ cells were examined by immunohistochemistry in cryostat sections of bronchial/nasal biopsies obtained from 33 SAs (21 frequent exacerbators [FEs]), 31 MAs (3 FEs), and 14 controls. IL-17F protein was also measured by ELISA in bronchial/nasal lysates and by immunohistochemistry in bronchial tissue obtained from subjects who died because of fatal asthma. Immunofluorescence/confocal microscopy was used for IL-17F colocalization.

RESULTS

Higher number (P < .05) of neutrophils, IL-17A⁺, IL-17F⁺, and IL-21⁺ cells in bronchial biopsies and higher numbers (P < .01) of IL-17F⁺ and IL-21⁺ cells in nasal biopsies were observed in SAs compared with MAs. Bronchial IL-17F⁺ cells correlated with bronchial neutrophils (r = 0.54), exacerbation rate (r = 0.41), and FEV₁ (r = -0.46). Nasal IL-17F⁺ cells correlated with bronchial IL-17F (r = 0.35), exacerbation rate (r = 0.47), and FEV₁ (r = -0.61). FEs showed increased number of bronchial neutrophils/eosinophils/CD4⁺/CD8⁺ cells and bronchial/nasal IL-17F⁺ cells. Receiver operating characteristic curve analysis evidenced predictive cutoff values of bronchial neutrophils and nasal/bronchial IL-17F for discriminating between asthmatics and controls, between MAs and SAs and between FEs and non-FEs. IL-17F protein increased in bronchial/nasal lysates of SAs and FEs and in bronchial tissue of fatal asthma. IL-17F colocalized in CD4⁺/CD8⁺ cells.

CONCLUSIONS

IL-17-related cytokines expression was amplified in bronchial/nasal mucosa of neutrophilic asthma prone to exacerbation, suggesting a pathogenic role of IL-17F in FEs.

Toxicity assessment of hydroxyapatite nanoparticles in rat liver cell model in vitro

Hydroxyapatite nanoparticles (HAP NPs) are widely used for preparations of biomedical and biotechnological fields such as drug delivery, gene therapy, and molecular imaging. However, the current toxicological knowledge about HAP NPs is relatively limited. The present study was designed to investigate the toxicity potentials of various concentrations (0–1000 µg cm−2) of HAP NPs in cultured primary rat hepatocytes. Cell viability was detected by 3-(4,5-dimethyl-thiazol-2-yl) 2,5-diphenyltetrazolium bromide (MTT) assay and lactate dehydrogenase (LDH) release, while total antioxidant capacity (TAC) and total oxidative stress (TOS) levels were determined to evaluate the oxidative injury. The DNA damage was also analyzed via scoring liver micronuclei rates and determining 8-oxo-2-deoxyguanosine (8-OH-dG) levels. The results of MTT and LDH assays showed that the higher concentrations of dispersed HAP NPs (300, 500, and 1000 µg cm−2) decreased cell viability. Also, HAP NPs increased TOS (500 and 1000 µg cm−2) levels and decreased TAC (300, 500, and 1000 µg cm−2) levels in cultured hepatocytes. On the basis of increasing doses, the NPs as depending on dose caused significant increases of the number of micronucleated hepatocytes and 8-OH-dG levels as compared to control culture. Furthermore, the highest concentration of HAP NPs (1000 µg cm−2) exhibited cytotoxic activity. Based on these results, HAP NPs have a dose-dependent toxic effect in rat hepatocytes. Further extensive research in this field is promising and reasonable.

COPD immunopathology

The immunopathology of chronic obstructive pulmonary disease (COPD) is based on the innate and adaptive inflammatory immune responses to the chronic inhalation of cigarette smoking. In the last quarter of the century, the analysis of specimens obtained from the lower airways of COPD patients compared with those from a control group of age-matched smokers with normal lung function has provided novel insights on the potential pathogenetic role of the different cells of the innate and acquired immune responses and their pro/anti-inflammatory mediators and intracellular signalling pathways, contributing to a better knowledge of the immunopathology of COPD both during its stable phase and during its exacerbations. This also has provided a scientific rationale for new drugs discovery and targeting to the lower airways. This review summarises and discusses the immunopathology of COPD patients, of different severity, compared with control smokers with normal lung function.

Bacterial-viral load and the immune response in stable and exacerbated COPD: significance and therapeutic prospects

Chronic obstructive pulmonary disease (COPD) is characterized by persistent airflow limitation and an abnormal inflammatory response of the lung. Bacteria and viruses are a major cause of COPD exacerbations and may contribute to COPD progression by perpetuating the inflammatory response in the airways. Bacterial variety diminishes with increasing COPD severity. Respiratory viruses can colonize the lower respiratory tract in stable COPD, altering the respiratory microbiome and facilitating secondary bacterial infections. In this review, we present the most updated information about the role of bacteria and viruses in stable and exacerbated COPD. In our opinion, to optimize therapeutic strategies, the dynamic events involving bacterial-viral infections and related immune response in COPD phenotypes need to be better clarified. Our paper would address these points that we consider of great importance for the clinical management of COPD.

Hsp10 nuclear localization and changes in lung cells response to cigarette smoke suggest novel roles for this chaperonin

Heat-shock protein (Hsp)10 is the co-chaperone for Hsp60 inside mitochondria, but it also resides outside the organelle. Variations in its levels and intracellular distribution have been documented in pathological conditions, e.g. cancer and chronic obstructive pulmonary disease (COPD). Here, we show that Hsp10 in COPD undergoes changes at the molecular and subcellular levels in bronchial cells from human specimens and derived cell lines, intact or subjected to stress induced by cigarette smoke extract (CSE). Noteworthy findings are: (i) Hsp10 occurred in nuclei of epithelial and lamina propria cells of bronchial mucosa from non-smokers and smokers; (ii) human bronchial epithelial (16HBE) and lung fibroblast (HFL-1) cells, in vitro, showed Hsp10 in the nucleus, before and after CSE exposure; (iii) CSE stimulation did not increase the levels of Hsp10 but did elicit qualitative changes as indicated by molecular weight and isoelectric point shifts; and (iv) Hsp10 nuclear levels increased after CSE stimulation in HFL-1, indicating cytosol to nucleus migration, and although Hsp10 did not bind DNA, it bound a DNA-associated protein.

Phospho-p38 MAPK expression in COPD patients and asthmatics and in challenged bronchial epithelium

BACKGROUND

The role of mitogen-activated protein kinases (MAPK) in regulating the inflammatory response in the airways of patients with chronic obstructive pulmonary disease (COPD) and asthmatic patients is unclear.

OBJECTIVES

To investigate the expression of activated MAPK in lungs of COPD patients and in bronchial biopsies of asthmatic patients and to study MAPK expression in bronchial epithelial cells in response to oxidative and inflammatory stimuli.

METHODS

Immunohistochemical expression of phospho (p)-p38 MAPK, p-JNK1 and p-ERK1/2 was measured in bronchial mucosa in patients with mild/moderate (n = 17), severe/very severe (n = 16) stable COPD, control smokers (n = 16), control non-smokers (n = 9), in mild asthma (n = 9) and in peripheral airways from COPD patients (n = 15) and control smokers (n = 15). Interleukin (IL)-8 and MAPK mRNA was measured in stimulated 16HBE cells.

RESULTS

No significant differences in p-p38 MAPK, p-JNK or p-ERK1/2 expression were seen in bronchial biopsies and peripheral airways between COPD and control subjects. Asthmatics showed increased submucosal p-p38 MAPK expression compared to COPD patients (p < 0.003) and control non-smokers (p < 0.05). Hydrogen peroxide (H₂O₂), cytomix (tumour necrosis factor-α + IL-1β + interferon-γ) and lipopolysaccharide (LPS) upregulated IL-8 mRNA at 1 or 2 h. p38 MAPKα mRNA was significantly increased after H₂O₂ and LPS treatment. JNK1 and ERK1 mRNA were unchanged after H₂O₂, cytomix or LPS treatments.

CONCLUSION

p-p38 MAPK expression is similar in stable COPD and control subjects but increased in the bronchi of mild asthmatics compared to stable COPD patients. p38 MAPK mRNA is increased after bronchial epithelial challenges in vitro. These data together suggest a potential role for this MAPK in Th2 inflammation and possibly during COPD exacerbations.

Molecular pathogenesis of cigarette smoking-induced stable COPD

Inflammation is a central feature of stable chronic obstructive pulmonary disease (COPD) and involves both activation of structural cells of the airways and the lungs and the activation and/or recruitment of infiltrating inflammatory cells. This results in enhanced expression of many pro-inflammatory proteins and reduced expression of some anti-inflammatory mediators. An altered protein expression is generally associated with concomitant changes in gene expression profiles in a cell-specific manner. Increased understanding of the role of transcription factors and of the signaling pathways leading to their activation in stable COPD will provide new targets to enable the development of potential anti-inflammatory drugs. Several new compounds targeting these pathways and/or transcription factors are now in development for the treatment of stable COPD. Furthermore, glucocorticoids drugs already in clinical use act through their own transcription factor, the glucocorticoid receptor, to control the expression of inflammatory and anti-inflammatory genes.

Zingiberene attenuates hydrogen peroxide-induced toxicity in neuronal cells

In this experimental design, we explored the neuroprotective potential of zingiberene (ZGB), a monocyclic sesquiterpene, in hydrogen peroxide (H2O2)-induced toxicity in newborn rat cerebral cortex cell cultures for the first time. The rats were exposed to H2O2 for 6 h to determine the oxidative stress levels. To evaluate cell viability, both 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide and lactate dehydrogenase assays were carried out. Total antioxidant capacity (TAC) and total oxidative stress (TOS) parameters were used to evaluate oxidative changes. Besides determining 8-hydroxy-2-deoxyguanosine (8-OH-dG) levels in vitro, single-cell gel electrophoresis was also performed to measure the resistance of neuronal DNA to H2O2- exposed rats. Our results showed that survival and TAC levels of the cells decreased, while TOS, 8-OH-dG levels and the mean values of the total scores of cells showing DNA damage increased in the H2O2 alone-treated cultures. But pretreatment of ZGB suppressed the cytotoxicity, genotoxicity and oxidative stress that were increased by H2O2. Based on these observations, it is suggested that the sesquiterpene ZGB can be used as a novel and natural potential therapeutic in counteracting oxidative damages in the field of neurodegenerative disorders.

Cytokine inhibition in the treatment of COPD

Cytokines play an important part in many pathobiological processes of chronic obstructive pulmonary disease (COPD), including the chronic inflammatory process, emphysema, and altered innate immune response. Proinflammatory cytokines of potential importance include tumor necrosis factor (TNF)-α, interferon-γ, interleukin (IL)-1β, IL-6, IL-17, IL-18, IL-32, and thymic stromal lymphopoietin (TSLP), and growth factors such as transforming growth factor-β. The current objectives of COPD treatment are to reduce symptoms, and to prevent and reduce the number of exacerbations. While current treatments achieve these goals to a certain extent, preventing the decline in lung function is not currently achievable. In addition, reversal of corticosteroid insensitivity and control of the fibrotic process while reducing the emphysematous process could also be controlled by specific cytokines. The abnormal pathobiological process of COPD may contribute to these fundamental characteristics of COPD, and therefore targeting cytokines involved may be a fruitful endeavor. Although there has been much work that has implicated various cytokines as potentially playing an important role in COPD, there have been very few studies that have examined the effect of specific cytokine blockade in COPD. The two largest studies that have been reported in the literature involve the use of blocking antibody to TNFα and CXCL8 (IL-8), and neither has provided benefit. Blocking the actions of CXCL8 through its CXCR2 receptor blockade was not successful either. Studies of antibodies against IL-17, IL-18, IL-1β, and TSLP are currently either being undertaken or planned. There is a need to carefully phenotype COPD and discover good biomarkers of drug efficacy for each specific target. Specific groups of COPD patients should be targeted with specific anticytokine therapy if there is evidence of high expression of that cytokine and there are features of the clinical expression of COPD that will respond.

Fibrosis markers and CRIM1 increase in chronic heart failure of increasing severity

BACKGROUND

Fibrosis suppressors/activators in chronic heart failure (CHF) is a topic of investigation.

AIM

To quantify serum levels of fibrosis regulators in CHF.

METHODS

ELISA tests were used to quantify fibrosis regulators, procollagen type-(PIP)I, (PIP)III, collagen-I, III, BMP1,2,3,7, SDF1α, CXCR4, fibulin 1,2,3, BMPER, CRIM1 and BAMBI in 66 CHF (NYHA class I, n = 9; II, n = 34; III n = 23), and in 14 controls.

RESULTS

In CHF, TGFβR2, PIPIII, SDF1α and CRIM1 were increased. PIPIII correlated with CRIM1.

CONCLUSIONS

The BMPs inhibitor CRIM1 is increased and correlates with higher levels of serum PIPIII showing an imbalance in favor of pro-fibrotic mechanisms in CHF.

Innate immunity but not NLRP3 inflammasome activation correlates with severity of stable COPD

Background

In models of COPD, environmental stressors induce innate immune responses, inflammasome activation and inflammation. However, the interaction between these responses and their role in driving pulmonary inflammation in stable COPD is unknown.

Objectives

To investigate the activation of innate immunity and inflammasome pathways in the bronchial mucosa and bronchoalveolar lavage (BAL) of patients with stable COPD of different severity and control healthy smokers and non-smokers.

Methods

Innate immune mediators (interleukin (IL)-6, IL-7, IL-10, IL-27, IL-37, thymic stromal lymphopoietin (TSLP), interferon γ and their receptors, STAT1 and pSTAT1) and inflammasome components (NLRP3, NALP7, caspase 1, IL-1β and its receptors, IL-18, IL-33, ST2) were measured in the bronchial mucosa using immunohistochemistry. IL-6, soluble IL-6R, sgp130, IL-7, IL-27, HMGB1, IL-33, IL-37 and soluble ST2 were measured in BAL using ELISA.

Results

In bronchial biopsies IL-27+ and pSTAT1+ cells are increased in patients with severe COPD compared with control healthy smokers. IL-7+ cells are increased in patients with COPD and control smokers compared with control non-smokers. In severe stable COPD IL-7R+, IL-27R+ and TSLPR+ cells are increased in comparison with both control groups. The NALP3 inflammasome is not activated in patients with stable COPD compared with control subjects. The inflammasome inhibitory molecules NALP7 and IL-37 are increased in patients with COPD compared with control smokers. IL-6 levels are increased in BAL from patients with stable COPD compared with control smokers with normal lung function whereas IL-1β and IL-18 were similar across all groups.

Conclusions

Increased expression of IL-27, IL-37 and NALP7 in the bronchial mucosa may be involved in progression of stable COPD.

Aerobic training and angiogenesis activation in patients with stable chronic heart failure: a preliminary report

The pathophysiology of chronic heart failure (CHF) involves multiple hystologic and molecular alterations. To determine the effects of physical training on circulating endothelial progenitor cells (EPCs), angiogenesis (angiogenin, angiopoietin-1 and -2, VEGF, Tie-2, SDF-1α) and inflammation (IL-6, CRP), we compared data obtained from 11 CHF pts before and after 3 months aerobic exercise training, to those from 10 non trained CHF pts (CHF-C group, age 64 + 2 years, NYHA 2). At the end of the study, EPCs count and AP-2 serum levels significantly increased in the CHF-TR group. These preliminary data suggest a significant effect of even a short program of physical training on angiogenic activation and endothelial dysfunction.

Expression of vascular remodelling markers in relation to bradykinin receptors in asthma and COPD

BACKGROUND

Vascular remodelling plays a central role in asthma and chronic obstructive pulmonary disease (COPD). Bradykinin (BK) is a vasoactive proinflammatory peptide mediating acute responses in asthma. We investigated the role of angiogenic factors in relation to BK receptors in asthma and COPD.

METHODS

Bronchial biopsies from 33 patients with COPD, 24 old (≥50 years) patients with (≥50 years) asthma, 18 old control smokers, 11 old control non-smokers, 15 young (≤40yrs) patients with (≤40 years) asthma and 10 young control non-smokers were immunostained for CD31, vascular endothelial growth factor-A (VEGF-A), angiogenin and BK receptors (B2R and B1R). Fibroblast and endothelial co-localisation of relevant molecules were performed by immunofluorescence. BK-induced VEGF-A and angiogenin release was studied (ELISA) in bronchial fibroblasts from subjects with asthma and COPD.

RESULTS

In bronchial lamina propria of old patients with asthma, CD31 and VEGF-A(+) cell numbers were higher than old control non-smokers (p<0.05). Angiogenin(+), B2R(+) and B1R(+) cell numbers in old patients with asthma were higher than in old control non-smokers, control smokers and patients with COPD (p<0.01). Angiogenin(+) cell numbers were higher in patients with COPD than both old control groups (p<0.05). In all patients with asthma the number of B2R(+) cells was positively related to the numbers of B1R(+) (rs=0.43), angiogenin(+) (rs=0.42) and CD31 cells (rs=0.46) (p<0.01). Angiogenin(+) cell numbers were negatively related to forced expiratory volume in 1 s (rs=-0.415, p=0.008). Double immunofluorescence revealed that CD31 cells of capillary vessels coexpressed B2R and that fibroblasts coexpressed B2R, VEGF-A and angiogenin. BK (10(-6)M) induced significant angiogenin release in fibroblasts from asthma and to a lesser extent in COPD.

CONCLUSIONS

Unlike COPD, this study suggests the involvement of BK receptors in bronchial vascular remodelling in asthma.

Isolation and characterization of CD276+/HLA-E+ human subendocardial mesenchymal stem cells from chronic heart failure patients: analysis of differentiative potential and immunomodulatory markers expression

Mesenchymal stem cells (MSCs) are virtually present in all postnatal organs as well as in perinatal tissues. MSCs can be differentiated toward several mature cytotypes and interestingly hold potentially relevant immunomodulatory features. Myocardial infarction results in severe tissue damage, cardiomyocyte loss, and eventually heart failure. Cellular cardiomyoplasty represents a promising approach for myocardial repair. Clinical trials using MSCs are underway for a number of heart diseases, even if their outcomes are hampered by low long-term improvements and the possible presence of complications related to cellular therapy administration. Therefore, elucidating the presence and role of MSCs that reside in the post-infarct human heart should provide essential alternatives for therapy. In the current article we show a novel method to reproducibly isolate and culture MSCs from the subendocardial zone of human left ventricle from patients undergoing heart transplant for post-infarct chronic heart failure (HSE-MSCs, human subendocardial mesenchymal stem cells). By using both immunocytochemistry and reverse transcriptase-polymerase chain reaction (RT-PCR), we demonstrated that these cells do express key MSCs markers and do express heart-specific transcription factors in their undifferentiated state, while lacking strictly cardiomyocyte-specific proteins. Moreover, these cells do express immunomodulatory molecules that should disclose their further potential in immune modulation processes in the post-infarct microenvironment. Another novel datum of potentially relevant interest is the expression of cardiac myosin heavy chain at nucclear level in HSE-MSCs. Standard MSCs trilineage differentiation experiments were also performed. The present paper adds new data on the basic biological features of heart-resident MSCs that populate the organ following myocardial infarction. The use of heart-derived MSCs to promote in-organ repair or as a cellular source for cardiomyoplasty is a fascinating and challenging task, which deserves further research efforts.

Convergent sets of data from in vivo and in vitro methods point to an active role of Hsp60 in chronic obstructive pulmonary disease pathogenesis

Background

It is increasingly clear that some heat shock proteins (Hsps) play a role in inflammation. Here, we report results showing participation of Hsp60 in the pathogenesis of chronic obstructive pulmonary diseases (COPD), as indicated by data from both in vivo and in vitro analyses.

Methods and Results

Bronchial biopsies from patients with stable COPD, smoker controls with normal lung function, and non-smoker controls were studied. We quantified by immunohistochemistry levels of Hsp10, Hsp27, Hsp40, Hsp60, Hsp70, Hsp90, and HSF-1, along with levels of inflammatory markers. Hsp10, Hsp40, and Hsp60 were increased during progression of disease. We found also a positive correlation between the number of neutrophils and Hsp60 levels. Double-immunostaining showed that Hsp60-positive neutrophils were significantly increased in COPD patients. We then investigated in vitro the effect on Hsp60 expression in bronchial epithelial cells (16HBE) caused by oxidative stress, a hallmark of COPD mucosa, which we induced with H₂O₂. This stressor determined increased levels of Hsp60 through a gene up-regulation mechanism involving NFkB-p65. Release of Hsp60 in the extracellular medium by the bronchial epithelial cells was also increased after H₂O₂ treatment in the absence of cell death.

Conclusions

This is the first report clearly pointing to participation of Hsps, particularly Hsp60, in COPD pathogenesis. Hsp60 induction by NFkB-p65 and its release by epithelial cells after oxidative stress can have a role in maintaining inflammation, e.g., by stimulating neutrophils activity. The data open new scenarios that might help in designing efficacious anti-inflammatory therapies centered on Hsp60 and applicable to COPD.

Wharton's jelly mesenchymal stem cells as candidates for beta cells regeneration: extending the differentiative and immunomodulatory benefits of adult mesenchymal stem cells for the treatment of type 1 diabetes

Mesenchymal stem cells (MSC) are uniquely capable of crossing germinative layers borders (i.e. are able to differentiate towards ectoderm-, mesoderm- and endoderm-derived cytotypes) and are viewed as promising cells for regenerative medicine approaches in several diseases. Type I diabetes therapy should potentially benefit from such differentiated cells: the search for alternatives to organ/islet transplantation strategies via stem cells differentiation is an ongoing task, significant goals having been achieved in most experimental settings (e.g. insulin production and euglycaemia restoration), though caution is still needed to ensure safe and durable effects in vivo. MSC are obtainable in high numbers via ex vivo culture and can be differentiated towards insulin-producing cells (IPC). Moreover, recent reports evidenced that MSC possess immunomodulatory activities (acting on both innate and acquired immunity effectors) which should result in a reduction of the immunogenicity of transplanted cells, thus limiting rejection. Moreover it has been proposed that MSC administration should be used to attenuate the autoimmune processes which lead to the destruction of beta cells. This review illustrates the recent advances made in differentiating human MSC to IPC. In particular, we compare the effectiveness of the differentiation protocols applied, the markers and functional assays used to characterize differentiated progeny, and the in vivo controls. We further speculate on how MSC derived from Wharton's jelly of human umbilical cord may represent a more promising regenerative medicine tool, as recently demonstrated for endoderm-derived organs (as liver) in human subjects, also considering their peculiar immunomodulatory features compared to other MSC populations.

High-resolution computed tomography quantitation of emphysema is correlated with selected lung function values in stable COPD

BACKGROUND

The literature shows conflicting results when high-resolution computed tomography (HRCT) scores of emphysema were correlated with different indices of airflow obstruction.

OBJECTIVES

We correlated HRCT scores of emphysema with different indices of airflow obstruction.

METHODS

We performed HRCT of the chest in 59 patients, all smokers or ex-smokers, with stable chronic obstructive pulmonary disease of different severity [GOLD stages I-IV; mean age ± SD 67.8 ± 7.3 years; pack/years 51.0 ± 34.6; percent predicted forced expiratory volume in 1 s (FEV(1)% predicted) 52.3 ± 17.6; post-bronchodilator FEV(1)% predicted 56.5 ± 19.1; FEV(1)/forced vital capacity (FVC) ratio 50.8 ± 10.2; post-bronchodilator FEV(1)/FVC ratio 51.6 ± 11.0; percent diffusion lung capacity for carbon monoxide (DLCO%) 59.2 ± 21.1; DLCO/percent alveolar volume (VA%) 54.5 ± 18.2; percent residual volume 163.0 ± 35.6; percent total lung capacity (TLC%) 113.2 ± 15; residual volume/TLC 1.44 ± 0.2]. All patients were in stable phase.

RESULTS

The mean ± SD visual emphysema score in all patients was 25.6 ± 25.4%. There was a weak but significant correlation between the percentage of pulmonary emphysema and numbers of pack/years (R = +0.31, p = 0.024). The percentage of emphysema was inversely correlated with the FEV(1)/FVC ratio before and after bronchodilator use (R = -0.44, p = 0.002, and R = -0.39, p = 0.005), DLCO% (R = -0.64, p = 0.0003) and DLCO/VA% (R = -0.68, p < 0.0001). A weak positive correlation was also found with TLC% (R = +0.28, p = 0.048). When patients with documented emphysema were considered separately, the best significant correlation observed was between DLCO/VA% and HRCT scan score (p = 0.007).

CONCLUSIONS

These data suggest that in patients with stable chronic obstructive pulmonary disease of varying severity, the presence of pulmonary emphysema is best represented by the impaired gas exchange capability of the respiratory system.

Stepwise increase of angiopoietin-2 serum levels is related to haemodynamic and functional impairment in stable chronic heart failure

BACKGROUND

A reciprocal link between inflammation, oxidative/nitrosative stress, and endothelial dysfunction has been postulated in chronic heart failure (CHF). The endothelial repair mechanisms involved remain to be determined. Our aim was to investigate whether there are detectable signs of ongoing angiogenesis in serum of CHF patients and to evaluate the correlation with indexes of haemodynamic and functional impairment.

METHODS AND RESULTS

Enzyme-linked immunosorbent assay tests were used to quantify angiogenin, angiopoietin-1, angiopoietin-2, vascular endothelial growth factor, Tie-2, and brain natriuretic peptide in serum of 87 patients with CHF of increasing severity according to New York Heart Association (NYHA; class I, n = 8; II, n = 45; and III, n = 34) and in 14 healthy subjects matched for age and sex. Angiogenin, angiopoietin-2, and Tie-2 were significantly increased in CHF of increasing severity (Kruskal-Wallis: p = 0.0004, p < 0.0001, and p = 0.017, respectively). Angiopoietin-2 was inversely correlated with the 6-min walking test (r = -0.65, p < 0.0001), peak oxygen consumption (VO(2max); r = -0.57, p = 0.0002), and deceleration time (r = -0.61, p < 0.0001). Multiple regression analysis showed that angiopoietin-2 was mainly associated with VO(2max) (p = 0.018). The angiopoietin-2 area under the receiver operating characteristic curve for CHF diagnosis was 0.94 (95% CI 0.88-0.99; p < 0.001).

CONCLUSIONS

These data demonstrate that angiopoietin-2 and selected serum markers of angiogenesis progressively increase with haemodynamic and functional decline in CHF.

Role of endothelial cell stress in the pathogenesis of chronic heart failure

Endothelial cells are key modulators of diverse physiological processes, and their impaired function is a cause of numerous cardiovascular diseases. Under physiologic condition, the reactive oxygen and nitrogen mediators in endothelia lead to the signal propagation of the initial stimulus, by forming molecules with a longer half-life like hydrogen peroxide. Hydrogen peroxide is the focus of growing attention in endothelial biology, and consequently the enzymes involved in its generation and clearance are viewed as novel mediators of great importance. In particular, among peroxidases, myeloperoxidase is recognized as a key enzyme, capable of impairing intracellular NO reservoirs as well as producing oxidized amino acids such as 3-chlorotyrosine or 3-nitrotyrosine. This process switches the functional pathways from normal signalling to a condition characterized by oxidative and/or nitrosative stress. Understanding the molecular mechanisms involved in these stress responses in endothelium will lead to better therapeutic strategies for oxidative stress-driven cardiovascular diseases.

Role of oxidative and nitrosative stress biomarkers in chronic heart failure

In this review, we present recent insights on chronic heart failure (CHF) and the potential role of tumor necrosis factor (TNF)-alpha, interleukins, myeloperoxidase (MPO), and nitrosative stress in the progression of this disease process. Reactive oxygen species (ROS) are produced as a consequence of aerobic metabolism. Under physiologic conditions, their unfavourable effect in causing oxidative damage is counteracted by antioxidants. An imbalance in favour of oxidants leads to oxidative stress, and contributes to myocyte apoptosis, direct negative inotropic effects, and reduced bioavailability of nitric oxide (NO). Together, these effects lead to impaired vasodilatation of the coronary, pulmonary and peripheral vascular beds. In patients with moderate to severe forms of CHF, TNF-alpha leads to the formation of nitrotyrosine and consumption of nitric oxide by virtue of activation of myeloperoxidase. Further studies are required to better elucidate the complex interaction of oxidative stress, endothelial dysfunction and inflammatory activation in CHF. Such insights would likely lead to development of better strategies for the assessment of the disease severity by monitoring of new bio-humoral indices and better treatment approaches.