Historical role of alpha-1-antitrypsin deficiency in respiratory and hepatic complications

Prognostic Biomarkers Based on Proteomic Technology in COPD: A Recent Review

Chronic obstructive pulmonary disease (COPD) is a common heterogeneous respiratory disease which is characterized by persistent and incompletely reversible airflow limitation. Due to the heterogeneity and phenotypic complexity of COPD, traditional diagnostic methods provide limited information and pose a great challenge to clinical management. In recent years, with the development of omics technologies, proteomics, metabolomics, transcriptomics, etc., have been widely used in the study of COPD, providing great help to discover new biomarkers and elucidate the complex mechanisms of COPD. In this review, we summarize the prognostic biomarkers of COPD based on proteomic studies in recent years and evaluate their association with COPD prognosis. Finally, we present the prospects and challenges of COPD prognostic-related studies. This review is expected to provide cutting-edge evidence in prognostic evaluation of clinical patients with COPD and to inform future proteomic studies on prognostic biomarkers of COPD.

Comparative pulmonary toxicity assessment of tungsten trioxide and tungsten trioxide hydrate nanoparticles

Tungsten trioxide (WO₃)-based nanoparticles (NPs) are gaining popularity because of their exciting potential for photocatalytic applications; however, the toxic potential of WO₃-based NPs remains a concern. In this study, we evaluated the toxic risk of WO₃ NPs and hydrated WO₃ NPs (WO₃·H₂O NPs) using lung cells and explored the underlying mechanism. WO₃ NPs and WO₃·H₂O NPs significantly decreased the number of viable cells (59.5 %-85.8 % of control) and promoted apoptosis in human alveolar basal epithelial A549 cells after a 24-h exposure. Both WO₃ NPs and WO₃·H₂O NPs reduced the expression of heme oxygenase-1 (0.15-0.33 folds of control) and superoxide dismutase 2 (0.31-0.66 folds of control) and increased reactive oxygen species production (1.4-2.6 folds of control) and 8-hydroxy-2'-deoxyguanosine accumulation (1.22-1.43 folds of control). The results showed that WO₃ NPs have higher cytotoxicity and oxidative potential than WO₃·H₂O NPs. In addition, the WO₃ NP cellular uptake rate was significantly higher than the WO₃·H₂O NPs uptake rate in pulmonary cells. The greater extent of oxidative adverse effects induced by WO₃-based NPs appears to be related to the enhanced particle uptake. WO₃ NPs and WO₃·H₂O NPs exposure led to the secretion of inflammatory factor interleukin 6 (1.63-3.42 folds of control). Decreases in serpin family A member 1 gene expression (0.28-0.58 folds of control) and increases in the oxidation of neutrophil elastase inhibitor (1.34-1.62 folds of control) in pulmonary cells also suggest that exposure to WO₃ NPs and WO₃·H₂O NPs raises the risk of developing chronic obstructive pulmonary disease. Taken together, our findings indicate that the toxic risk of WO₃ NPs and WO₃·H₂O NPs must be considered when manufacturing and applying WO₃-based NPs.

Pulmonary toxicity of actual alveolar deposition concentrations of ultrafine particulate matters in human normal bronchial epithelial cell

Air pollution is a major worldwide concern, and exposure to particulate matter (PM) can increase the risks of pulmonary diseases. Normal human bronchial epithelial cells were applied to clarify the role of ultrafine PM (UFPM) in the pathogenesis of pulmonary toxic effects with realistic alveolar deposition doses. The UFPM used in this research originated from vehicular emissions and coal combustion. UFPM exposure of up to 72 h was found to induce significant time- and concentration-dependent decreases in cell viability. Exposure to UFPM increased reactive oxygen species (ROS) accumulation through heme oxygenase-1 (HO-1) inhibition and induced massive oxidative stress that increased the interleukin-8 (IL-8) expression. UFPM also reduced the pulmonary trans-epithelial electrical resistance through the depletion of zonula occludens (ZO) proteins. Finally, UFPM decreased the α1-antitrypsin (A1AT) expression, which implies high risk of chronic obstructive pulmonary disease (COPD). The evidence demonstrates that exposure to UFPM, even at very low concentrations, may affect the functions of the respiratory system.

Methods of Purification and Application Procedures of Alpha1 Antitrypsin: A Long-Lasting History

The aim of the present report is to review the literature addressing the methods developed for the purification of alpha1-antitrypsin (AAT) from the 1950s to the present. AAT is a glycoprotein whose main function is to protect tissues from human neutrophil elastase (HNE) and other proteases released by neutrophils during an inflammatory state. The lack of this inhibitor in human serum is responsible for the onset of alpha1-antitrypsin deficiency (AATD), which is a severe genetic disorder that affects lungs in adults and for which there is currently no cure. Being used, under special circumstances, as a medical treatment of AATD in the so-called “replacement” therapy (consisting in the intravenous infusion of the missing protein), AAT is a molecule with a lot of therapeutic importance. For this reason, interest in AAT purification from human plasma or its production in a recombinant version has grown considerably in recent years. This article retraces all technological advances that allowed the manufacturers to move from a few micrograms of partially purified AAT to several grams of highly purified protein. Moreover, the chronic augmentation and maintenance therapy in individuals with emphysema due to congenital AAT deficiency (current applications in the clinical setting) is also presented.

A Stress Buffering Perspective on the Progression of Alpha-1 Antitrypsin Deficiency

This study used the stress buffering perspective to identify social resources, including social network support, having a high quality marriage, and spousal support, that protect against deleterious effects of the progression of Alpha-1 antitrypsin deficiency (AATD) on quality of life. Participants included 130 married adults living with AATD. We measured participants' quality of life in three ways: perceived stress, life satisfaction, and perceptions of social stigma. The results suggested that disease progression corresponded positively with perceived stress and negatively with life satisfaction. Social network support moderated the association between disease progression and perceived stress and social stigma, and spousal support moderated the association between disease progression and perceived stress and life satisfaction. Marital quality was not a significant moderator. The discussion highlights the stress buffering effects of social support from close others.

Functional characterization of the mouse Serpina1 paralog DOM-7

The generation of authentic mouse-models for human α1-antitrypsin (A1AT)-deficiency is difficult due to the high complexity of the mouse Serpina1 gene locus. Depending on the exact mouse strain, three to five paralogs are expressed, with different proteinase inhibitory properties. Nowadays with CRISPR-technology, genome editing of complex genomic loci is feasible and could be employed for the generation of A1AT-deficiency mouse models. In preparation of a CRISPR/Cas9-based genome-engineering approach we identified cDNA clones with a functional CDS for the Serpina1-paralog DOM-7. Here, we show that DOM-7 functionally inhibits neutrophil elastase (ELANE) and chymotrypsin, and therefore needs to be considered when aiming at the generation of A1AT-deficient models.

The Multifaceted Effects of Alpha1-Antitrypsin on Neutrophil Functions

Neutrophils are the predominant immune cells in human blood possessing heterogeneity, plasticity and functional diversity. The activation and recruitment of neutrophils into inflamed tissue in response to stimuli are tightly regulated processes. Alpha1-Antitrypsin (AAT), an acute phase protein, is one of the potent regulators of neutrophil activation via both -protease inhibitory and non-inhibitory functions. This review summarizes our current understanding of the effects of AAT on neutrophils, illustrating the interplay between AAT and the key effector functions of neutrophils.

Investigating Married Adults' Communal Coping with Genetic Health Risk and Perceived Discrimination

Increased genetic testing in personalized medicine presents unique challenges for couples, including managing disease risk and potential discrimination as a couple. This study investigated couples' conflicts and support gaps as they coped with perceived genetic discrimination. We also explored the degree to which communal coping was beneficial in reducing support gaps, and ultimately stress. Dyadic analysis of married adults (N = 266, 133 couples), in which one person had the genetic risk for serious illness, showed that perceived discrimination predicted more frequent conflicts about AATD-related treatment, privacy boundaries, and finances, which, in turn, predicted wider gaps in emotion and esteem support, and greater stress for both spouses. Communal coping predicted lower support gaps for both partners and marginally lower stress.

Role of Proteases in Lung Disease: A Brief Overview

Proteases play an important role in health and disease of the lung. In the normal lungs, proteases maintain their homeostatic functions that regulate processes like its regeneration and repair. Dysregulation of proteases–antiproteases balance is crucial in the manifestation of different types of lung diseases. Chronic inflammatory lung pathologies are associated with a marked increase in protease activities. Thus, in addition to protease activities, inhibition of anti-proteolytic control mechanisms are also important for effective microbial infection and inflammation in the lung. Herein, we briefly summarize the role of different proteases and to some extent antiproteases in regulating a variety of lung diseases.

Polycyclic aromatic hydrocarbons are associated with increased risk of chronic obstructive pulmonary disease during haze events in China

Although exposure to particulate matter with a diameter of <2.5μm (PM_2.5) is associated with chronic obstructive pulmonary disease (COPD), the major components of PM_2.5 in COPD pathogenesis are controversial. Here we employed the human lung epithelial cell line BEAS-2B to elucidate the association between COPD and the organic and water-soluble components of PM_2.5. We found that the PM_2.5 organic extract was a potential major risk factor for pulmonary epithelial barrier dysfunction through the depletion of proteins from the zonula occludens. This extract induced severe oxidative stress that increased DNA damage and the production of proinflammatory cytokines by BEAS-2B cells as well as decreased α1-antitrypsin expression, suggesting a mechanism that increases the risk of COPD. These effects were mainly mediated by polycyclic aromatic hydrocarbons (PAHs) through the aryl hydrocarbon receptor pathway. PAHs with high benzo(a)pyrene (BaP)-equivalent concentrations, but not major PAH components, have an increased risk of causing COPD, suggesting that BaP-equivalent concentrations represent a PM_2.5-induced COPD risk metric, which may contribute to provide a rationale for the remediation of air pollution.

Practical Methods for Assessing Emphysema Severity Based on Estimation of Linear Mean Intercept (Lm) in the Context of Animal Models of Alpha-1 Antitrypsin Deficiency

Alpha-1 antitrypsin deficiency is typified by panacinar emphysema in humans. Whilst animal models of (α1A-TD) that more accurately reflect the histology and molecular pathology of α1A-TD are in development, it is timely to discuss methods to assess emphysema severity. Several methods exist to quantify emphysema from histologic sections, including linear mean intercept (Lm), equivalent diameters (D) or their statistical derivatives (D2), and more recently probability models of D2 ("severity index"). Given proper attention to lung inflation, reference volume, and random sampling, Lm determined by intersect point counting provides a robust analytical tool to quantify emphysema severity. Details of lung preparation, processing for random sampling, and batch processing of prescreened images are provided herein.

Intermittent Hypoxia Contributes to the Lung Damage by Increased Oxidative Stress, Inflammation, and Disbalance in Protease/Antiprotease System

INTRODUCTION

Intermittent hypoxia as a surrogate of obstructive sleep apnea is associated with different cardiovascular complications. However, the effects of intermittent hypoxia on the lung tissue are less known. Therefore, the aim of our present study was to investigate if intermittent hypoxia may influence oxidative stress, inflammation, and protease/antiprotease system in the lung. Additionally, potential protective properties of anti-inflammatory and anti-oxidative drugs have been evaluated.

METHODS

32 mice were divided into four groups: (1) intermittent hypoxia, (2) intermittent hypoxia with infliximab, (3) intermittent hypoxia with L-glutathione, and (4) normoxia. After 4 weeks, lungs and blood were collected. Levels of reactive oxygen species in the lung were calculated by L-O12-enhanced chemiluminescence. CD68-positive lung macrophages were detected by immunofluorescence. Concentrations of elastase and desmosine in lung and of alpha-1-antitrypsin in blood were calculated by means of enzyme-linked immunosorbent assay.

RESULTS

Compared to a control, intermittent hypoxia augmented the release of free oxygen radicals, expression of CD68+ macrophages, and concentration of elastase in the lung tissue. Despite increased blood levels of protective alpha-1-antitrypsin, concentrations of desmosine-degradation product of elastin were higher versus control. The application of anti-inflammatory infliximab und anti-oxidative L-glutathione prevented at least partly the above-observed hypoxia-associated changes.

CONCLUSIONS

Intermittent hypoxia contributes to the lung damage by increased oxidative stress, inflammation, and disbalance in protease/antiprotease system. Infliximab and L-glutathione may prevent adverse hypoxia-induced lung alternations.