Oxidative stress in chronic obstructive pulmonary disease: a lung and systemic process

Progesterone (P4) ameliorates cigarette smoke-induced chronic obstructive pulmonary disease (COPD)

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory lung disease associated with high morbidity and mortality worldwide. Oxidative injury and mitochondrial dysfunction in the airway epithelium are major events in COPD progression.

METHODS AND RESULTS

The therapeutic effects of Progesterone (P4) were investigated in vivo and in vitro in this study. In vivo, in a cigarette smoke (CS) exposure-induced COPD mouse model, P4 treatment significantly ameliorated CS exposure-induced physiological and pathological characteristics, including inflammatory cell infiltration and oxidative injury, in a dose-dependent manner. The c-MYC/SIRT1/PGC-1α pathway is involved in the protective function of P4 against CS-induced COPD. In vitro, P4 co-treatment significantly ameliorated H2O2-induced oxidative injury and mitochondrial dysfunctions by promoting cell proliferation, increasing mitochondrial membrane potential, decreasing ROS levels and apoptosis, and increasing ATP content. Moreover, P4 co-treatment partially attenuated H2O2-caused inhibition in Nrf1, Tfam, Mfn1, PGR-B, c-MYC, SIRT1, and PGC-1α levels. In BEAS-2B and ASM cells, the c-MYC/SIRT1 axis regulated P4's protective effects against H2O2-induced oxidative injury and mitochondrial dysfunctions.

CONCLUSION

P4 activates the c-MYC/SIRT1 axis, ameliorating CS-induced COPD and protecting both airway epithelial cells and smooth muscle cells against H2O2-induced oxidative damage. PGC-1α and downstream mitochondrial signaling pathways might be involved.

Immunoactive signatures of circulating tRNA- and rRNA-derived RNAs in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is the most prevalent lung disease, and macrophages play a central role in the inflammatory response in COPD. We here report a comprehensive characterization of circulating short non-coding RNAs (sncRNAs) in plasma from patients with COPD. While circulating sncRNAs are increasingly recognized for their regulatory roles and biomarker potential in various diseases, the conventional RNA-seq method cannot fully capture these circulating sncRNAs due to their heterogeneous terminal structures. By pre-treating the plasma RNAs with T4 polynucleotide kinase, which converts all RNAs to those with RNA-seq susceptible ends (5'-phosphate and 3'-hydroxyl), we comprehensively sequenced a wide variety of non-microRNA sncRNAs, such as 5'-tRNA halves containing a 2',3'-cyclic phosphate. We discovered a remarkable accumulation of the 5'-half derived from tRNA ValCAC in plasma from COPD patients, whereas the 5'-tRNA GlyGCC half is predominant in healthy donors. Further, the 5'-tRNA ValCAC half activates human macrophages via Toll-like receptor 7 and induces cytokine production. Additionally, we identified circulating rRNA-derived fragments that were upregulated in COPD patients and demonstrated their ability to induce cytokine production in macrophages. Our findings provide evidence of circulating, immune-active sncRNAs in patients with COPD, suggesting that they serve as inflammatory mediators in the pathogenesis of COPD.

Association of the methionine sulfoxide reductase A rs10903323 gene polymorphism with functional activity and oxidative modification of alpha-1-antitrypsin in COPD patients

OBJECTIVE

Chronic obstructive pulmonary disease (COPD) is multi-factorial disorder which results from environmental influences and genetic factors. We aimed to investigate whether methionine sulfoxide reductase A (MSRA) rs10903323 gene polymorphism is associated with COPD development and severity in Serbian adult population.

METHODS

The study included 155 patients with COPD and 134 healthy volunteers. Genotyping was determined performing home-made polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The difference between the inhibitory activities of normal and oxidized Alpha-1-Antitrypsin (A1AT) against elastase and trypsin was used for determination of Oxidized Alpha-1-Antitrypsin (OxyA1AT) (expressed as % and g/L). Functional activity of A1AT was presented as a specific inhibitor activity to elastase (SIA-Elastase, kU/g).

RESULTS

Frequencies of the genotypes AA, AG and GG were 80.0%, 20.0%, 0% in COPD patients and 80.5%, 18.5% and 1.5% in the control group, and there was no significant difference in genotype or allele distributions between groups. Serum level of A1AT (g/L) and OxyA1AT was significantly higher in COPD patients than in the control group, but functional activity of A1AT (SIA-Elastase) was significantly lower in COPD patients than in the control group. In COPD group, increased level of OxyA1AT was present in G allele carriers who were smokers relative to G allele carriers who were not smokers. In the smoker group of patients with severe and very severe COPD (GOLD3+4), significant increase in OxyA1AT level was present in G allele carriers compared to AA homozygotes.

CONCLUSION

These findings suggest that MSRA rs10903323 gene polymorphism is probably not a risk for COPD by itself but could represent a COPD modifier, since minor, G allele, is associated with an increased level of oxidized A1AT, indicating impaired ability of MSRA to repair oxidized A1AT in COPD-smokers, and in severe form of COPD.

Efficacy and Mechanisms of Natural Products as Therapeutic Interventions for Chronic Respiratory Diseases

Chronic respiratory diseases are long-term conditions affecting the airways and other lung components that are characterized by a high prevalence, disability rate, and mortality rate. Further optimization of their treatment is required. Natural products, primarily extracted from organisms, possess specific molecular and structural formulas as well as distinct chemical and physical properties. These characteristics grant them the advantages of safety, gentleness, accessibility, and minimal side effects. The numerous advances in the use of natural products for treating chronic respiratory diseases have provided a steady source of motivation for new drug research and development. In this paper, we introduced the pathogenesis of chronic respiratory diseases and natural products. Furthermore, we classified natural products according to their mechanism for treating chronic respiratory diseases and describe the ways in which these products can alleviate the pathological symptoms. Simultaneously, we elaborate on the signal transduction pathways and biological impacts of natural products' targeting. Additionally, we present future prospects for natural products, considering their combination treatment approaches and administration methods. The significance of this review extends to both the research on preventing and treating chronic respiratory diseases, as well as the advancement of novel drug development in this field.

Comparison of the effects of active and passive smoking of tobacco cigarettes, electronic nicotine delivery systems and tobacco heating products on the expression and secretion of oxidative stress and inflammatory response markers. A systematic review

OBJECTIVES

This work attempts to summarize current knowledge on the effects of active and passive smoking of cigarettes, electronic nicotine delivery systems and tobacco heating products on the expression and secretion of oxidative stress and inflammatory response mediators, and on their possible impact on chronic obstructive pulmonary disease development.

MATERIALS AND METHODS

The literature was searched by the terms: 'smoking', 'active smoking', 'passive smoking', 'main-stream smoke', 'side-stream smoke', 'secondhand smoke', 'cigarette' 'THP', 'tobacco heating product', 'ENDS', 'electronic nicotine delivery system', 'e-cigarette', 'electronic cigarette', oxidative stress', inflammatory response' and 'gene expression'.

RESULTS

Cigarette smoking (active and passive) induces oxidative stress and inflammatory response in the airways. We present the effect of active smoking of e-cigarettes (EC) and heat-not-burn (HnB) products on the increased expression and secretion of oxidative stress and inflammatory response markers. However, there is only a limited number of studies on the effect of their second-hand smoking, and those available mainly describe aerosol composition.

DISCUSSION

The literature provides data which confirm that active and passive cigarette smoking induces oxidative stress and inflammatory response in the airways and is a key risk factor of COPD development. Currently, there is a limited number of data about ENDS and THP active and passive smoking effects on the health of smokers and never-smokers. It is particularly important to assess the effect of such products during long-term use by never-smokers who choose them as the first type of cigarettes, and for never-smokers who are passively exposed to their aerosol.

Chronic Obstructive Pulmonary Disease and Its Effect on Red Blood Cell Indices

Chronic obstructive pulmonary disease (COPD) constitutes a set of heterogeneous symptoms affecting millions of people worldwide. The associated comorbidities developing in COPD involve dysregulation in physiological pathways resulting from systemic inflammation in respiratory airways. In addition to mentioning the pathophysiology, stages, and consequences of COPD, this paper also defines red blood cell (RBC) indices such as hemoglobin, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin concentration, red blood cell distribution width, and RBC count. It explains the role of RBC indices and RBC structural abnormalities with disease severity and exacerbations in COPD patients. Although many factors have been studied as a marker of morbidity and mortality for COPD patients, RBC indices have emerged as revolutionary evidence. Therefore, the effectiveness of evaluating RBC indices in COPD patients and their importance as a negative predictor of survival, mortality, and clinical outcomes have been debated through rigorous literature reviews. Furthermore, the prevalence, mechanisms of development, and prognosis of underlying anemia and polycythemia in COPD have also been evaluated, with anemia most significantly associated with COPD. Therefore, more studies should be conducted to address underlying anemia in COPD patients to lessen the severity and disease burden. Correcting the RBC indices in COPD patients remarkably impacts the quality of life and reduces in-patient admissions, healthcare resource utilization, and costs. Hence, it is noteworthy to understand the significance of considering RBC indices while dealing with COPD patients.

The therapeutic potential of quercetin for cigarette smoking-induced chronic obstructive pulmonary disease: a narrative review

Quercetin is a flavonoid with antioxidant and anti-inflammatory properties. Quercetin has potentially beneficial therapeutic effects for several diseases, including cigarette smoking-induced chronic obstructive pulmonary disease (CS-COPD). Many studies have shown that quercetin's antioxidant and anti-inflammatory properties have positive therapeutic potential for CS-COPD. In addition, quercetin's immunomodulatory, anti-cellular senescence, mitochondrial autophagy-modulating, and gut microbiota-modulating effects may also have therapeutic value for CS-COPD. However, there appears to be no review of the possible mechanisms of quercetin for treating CS-COPD. Moreover, the combination of quercetin with common therapeutic drugs for CS-COPD needs further refinement. Therefore, in this article, after introducing the definition and metabolism of quercetin, and its safety, we comprehensively presented the pathogenesis of CS-COPD related to oxidative stress, inflammation, immunity, cellular senescence, mitochondrial autophagy, and gut microbiota. We then reviewed quercetin's anti-CS-COPD effects, performed by influencing these mechanisms. Finally, we explored the possibility of using quercetin with commonly used drugs for treating CS-COPD, providing a basis for future screening of excellent drug combinations for treating CS-COPD. This review has provided meaningful information on quercetin's mechanisms and clinical use in treating CS-COPD.

Interaction Of Inflammatory Parameters And Thiol/Disulfide System Of Antioxidant Protection In Chronic Obstructive Pulmonary Disease

Introduction — Increased incidence and prevalence of chronic obstructive pulmonary disease (COPD) provides rationale for describing the disease progression mechanism, considering the interaction of key participants of this process. The objective of our study was to establish the dysfunction parameters of thiol/disulfide system components and adaptive immunity unit in patients with stable chronic obstructive pulmonary disease (COPD). Material and Methods — We examined patients with stable COPD of moderate (62 subjects) or severe (50 subjects) grades. The control group included 32 subjects. Prooxidant and antioxidant markers of oxidative stress were investigated with ELISA. We determined cytokine levels in blood plasma and the number of T helper cells expressing IL-6R with flow cytometry (BD FACSCanto II, USA). Correlation pleiads sensu Terentiev were employed to visualize the data. Results — Changes in both antioxidant and cytokine status of subjects with COPD of varying severity grades implied the progression of systemic inflammation in conditions of uncontrolled activation of adaptive immunity unit rather than just a shift in the peroxide balance and an increase in oxygen metabolites. Conclusion — Accumulation of biomolecule peroxidation products, imbalance in the prooxidant-antioxidant system, and a change in pathogenetic mechanism of inflammation could lead to an aggravated course of bronchopulmonary pathology.

Analysis of the Clinical Efficacy and Molecular Mechanism of Xuefu Zhuyu Decoction in the Treatment of COPD Based on Meta-Analysis and Network Pharmacology

Background

Chronic obstructive pulmonary disease (COPD) is becoming a major public health burden worldwide. It is urgent to explore more effective and safer treatment strategy for COPD. Notably, Xuefu Zhuyu Decoction (XFZYD) is widely used to treat respiratory system diseases, including COPD, in China.

Objective

This study is aimed at comprehensively evaluating the therapeutic effects and molecular mechanism of XFZYD on COPD.

Methods

Original clinical studies were searched from eight literature databases. Meta-analysis was conducted using the Review Manager software (version 5.4.1). Network pharmacology and molecular docking experiments were utilized to explore the mechanisms of action of XFZYD.

Results

XFZYD significantly enhanced the efficacy of clinical treatment and improved the pulmonary function and hypoventilation of COPD patients. In addition, XFZYD significantly improved the hypercoagulability of COPD patients. The subgroup analysis suggested that XFZYD exhibited therapeutic effects on both stable and acute exacerbation of COPD. XFZYD exerted its therapeutic effects on COPD through multicomponent, multitarget, and multipathway characteristics. The intervention of the PI3K-AKT pathway may be the critical mechanism.

Conclusion

The application of XFZYD based on symptomatic relief and supportive treatment is a promising clinical decision. More preclinical and clinical studies are still needed to evaluate the safety and therapeutic effects of long-term use of XFZYD on COPD.

Glutathione: A Samsonian life-sustaining small molecule that protects against oxidative stress, ageing and damaging inflammation

Many local and systemic diseases especially diseases that are leading causes of death globally like chronic obstructive pulmonary disease, atherosclerosis with ischemic heart disease and stroke, cancer and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causing coronavirus disease 19 (COVID-19), involve both, (1) oxidative stress with excessive production of reactive oxygen species (ROS) that lower glutathione (GSH) levels, and (2) inflammation. The GSH tripeptide (γ- L-glutamyl-L-cysteinyl-glycine), the most abundant water-soluble non-protein thiol in the cell (1-10 mM) is fundamental for life by (a) sustaining the adequate redox cell signaling needed to maintain physiologic levels of oxidative stress fundamental to control life processes, and (b) limiting excessive oxidative stress that causes cell and tissue damage. GSH activity is facilitated by activation of the Kelch-like ECH-associated protein 1 (Keap1)-Nuclear factor erythroid 2-related factor 2 (Nrf2)-antioxidant response element (ARE) redox regulator pathway, releasing Nrf2 that regulates expression of genes controlling antioxidant, inflammatory and immune system responses. GSH exists in the thiol-reduced (>98% of total GSH) and disulfide-oxidized (GSSG) forms, and the concentrations of GSH and GSSG and their molar ratio are indicators of the functionality of the cell. GSH depletion may play a central role in inflammatory diseases and COVID-19 pathophysiology, host immune response and disease severity and mortality. Therapies enhancing GSH could become a cornerstone to reduce severity and fatal outcomes of inflammatory diseases and COVID-19 and increasing GSH levels may prevent and subdue these diseases. The life value of GSH makes for a paramount research field in biology and medicine and may be key against systemic inflammation and SARS-CoV-2 infection and COVID-19 disease. In this review, we emphasize on (1) GSH depletion as a fundamental risk factor for diseases like chronic obstructive pulmonary disease and atherosclerosis (ischemic heart disease and stroke), (2) importance of oxidative stress and antioxidants in SARS-CoV-2 infection and COVID-19 disease, (3) significance of GSH to counteract persistent damaging inflammation, inflammaging and early (premature) inflammaging associated with cell and tissue damage caused by excessive oxidative stress and lack of adequate antioxidant defenses in younger individuals, and (4) new therapies that include antioxidant defenses restoration.

Progress in non-viral localized delivery of siRNA therapeutics for pulmonary diseases

Emerging therapies based on localized delivery of siRNA to lungs have opened up exciting possibilities for treatment of different lung diseases. Localized delivery of siRNA to lungs has shown to result in severalfold higher lung accumulation than systemic route, while minimizing non-specific distribution in other organs. However, to date, only 2 clinical trials have explored localized delivery of siRNA for pulmonary diseases. Here we systematically reviewed recent advances in the field of pulmonary delivery of siRNA using non-viral approaches. We firstly introduce the routes of local administration and analyze the anatomical and physiological barriers towards effective local delivery of siRNA in lungs. We then discuss current progress in pulmonary delivery of siRNA for respiratory tract infections, chronic obstructive pulmonary diseases, acute lung injury, and lung cancer, list outstanding questions, and highlight directions for future research. We expect this review to provide a comprehensive understanding of current advances in pulmonary delivery of siRNA.

Aryl Hydrocarbon Receptor in Oxidative Stress as a Double Agent and Its Biological and Therapeutic Significance

The aryl hydrocarbon receptor (AhR) has long been implicated in the induction of a battery of genes involved in the metabolism of xenobiotics and endogenous compounds. AhR is a ligand-activated transcription factor necessary for the launch of transcriptional responses important in health and disease. In past decades, evidence has accumulated that AhR is associated with the cellular response to oxidative stress, and this property of AhR must be taken into account during investigations into a mechanism of action of xenobiotics that is able to activate AhR or that is susceptible to metabolic activation by enzymes encoded by the genes that are under the control of AhR. In this review, we examine various mechanisms by which AhR takes part in the oxidative-stress response, including antioxidant and prooxidant enzymes and cytochrome P450. We also show that AhR, as a participant in the redox balance and as a modulator of redox signals, is being increasingly studied as a target for a new class of therapeutic compounds and as an explanation for the pathogenesis of some disorders.

Human epididymis protein 4 aggravates airway inflammation and remodeling in chronic obstructive pulmonary disease

Background

Chronic obstructive pulmonary disease (COPD) is a progressive disease characterized by chronic inflammation and airway remodeling. Human epididymis protein 4 (HE4) plays a critical role in various inflammatory or fibrotic diseases. However, the role of HE4 in COPD remains unidentified.

Methods

HE4 expression was determined in the lung tissues from COPD patients and cigarette smoke (CS)-exposed mice using immunohistochemical staining, qPCR, or western blot. The plasma level of HE4 was detected by ELISA. The regulations of HE4 in the expressions of CS extract (CSE)-induced inflammatory cytokines in human bronchial epithelial cells (HBE) were investigated through knockdown or overexpression of HE4. The role of secretory HE4 (sHE4) in the differentiation and proliferation in human pulmonary fibroblast cells (HPF) was explored via qPCR, western blot, CCK8 assay or 5-ethynyl-2′-deoxyuridine (EdU) staining. The probe of related mechanism in CSE-induced HE4 increase in HBE was conducted by administrating N-acetylcysteine (NAC).

Results

HE4 was up-regulated in both the lung tissue and plasma of COPD patients relative to controls, and the plasma HE4 was negatively associated with lung function in COPD patients. The same enhanced HE4 expression was verified in CS-exposed mice and CSE-induced HBE, but CSE failed to increase HE4 expression in HPF. In vitro experiments showed that reducing HE4 expression in HBE alleviated CSE-induced IL-6 release while overexpressing HE4 facilitated IL-6 expression, mechanistically through affecting phosphorylation of NFκB-p65, whereas intervening HE4 expression had no distinctive influence on IL-8 secretion. Furthermore, we confirmed that sHE4 promoted fibroblast-myofibroblast transition, as indicated by promoting the expression of fibronectin, collagen I and α-SMA via phosphorylation of Smad2. EdU staining and CCK-8 assay demonstrated the pro-proliferative role of sHE4 in HPF, which was further confirmed by enhanced expression of survivin and PCNA. Pretreatment of NAC in CSE or H₂O₂-induced HBE mitigated HE4 expression.

Conclusions

Our study indicates that HE4 may participate in airway inflammation and remodeling of COPD. Cigarette smoke enhances HE4 expression and secretion in bronchial epithelium mediated by oxidative stress. Increased HE4 promotes IL-6 release in HBE via phosphorylation of NFκB-p65, and sHE4 promotes fibroblastic differentiation and proliferation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-022-02040-7.

The Aryl Hydrocarbon Receptor (AHR): A Novel Therapeutic Target for Pulmonary Diseases?

The aryl hydrocarbon receptor (AHR) is a cytoplasmic transcription factor that is well-known for regulating xenobiotic metabolism. Studies in knockout and transgenic mice indicate that the AHR plays a vital role in the development of liver and regulation of reproductive, cardiovascular, hematopoietic, and immune homeostasis. In this focused review on lung diseases associated with acute injury and alveolar development, we reviewed and summarized the current literature on the mechanistic role(s) and therapeutic potential of the AHR in acute lung injury, chronic obstructive pulmonary disease, and bronchopulmonary dysplasia (BPD). Pre-clinical studies indicate that endogenous AHR activation is necessary to protect neonatal and adult lungs against hyperoxia- and cigarette smoke-induced injury. Our goal is to provide insight into the high translational potential of the AHR in the meaningful management of infants and adults with these lung disorders that lack curative therapies.

Current views in chronic obstructive pulmonary disease pathogenesis and management

Chronic obstructive pulmonary disease (COPD) is a progressive lung dysfunction caused mainly by inhaling toxic particles and cigarette smoking (CS). The continuous exposure to ruinous molecules can lead to abnormal inflammatory responses, permanent damages to the respiratory system, and irreversible pathological changes. Other factors, such as genetics and aging, influence the development of COPD. In the last decade, accumulating evidence suggested that mitochondrial alteration, including mitochondrial DNA damage, increased mitochondrial reactive oxygen species (ROS), abnormal autophagy, and apoptosis, have been implicated in the pathogenesis of COPD. The alteration can also extend to epigenetics, namely DNA methylation, histone modification, and non-coding RNA. This review will discuss the recent progressions in COPD pathology, pathophysiology, and molecular pathways. More focus will be shed on mitochondrial and epigenetic variations related to COPD development and the role of nanomedicine as a potential tool for the prevention and treatment of this disease.

The Role of Extracellular Vesicles as a Shared Disease Mechanism Contributing to Multimorbidity in Patients With COPD

Chronic obstructive pulmonary disease (COPD) is one of the leading causes of death worldwide. Individuals with COPD typically experience a progressive, debilitating decline in lung function as well as systemic manifestations of the disease. Multimorbidity, is common in COPD patients and increases the risk of hospitalisation and mortality. Central to the genesis of multimorbidity in COPD patients is a self-perpetuating, abnormal immune and inflammatory response driven by factors including ageing, pollutant inhalation (including smoking) and infection. As many patients with COPD have multiple concurrent chronic conditions, which require an integrative management approach, there is a need to greater understand the shared disease mechanisms contributing to multimorbidity. The intercellular transfer of extracellular vesicles (EVs) has recently been proposed as an important method of local and distal cell-to-cell communication mediating both homeostatic and pathological conditions. EVs have been identified in many biological fluids and provide a stable capsule for the transfer of cargo including proteins, lipids and nucleic acids. Of these cargo, microRNAs (miRNAs), which are short 17-24 nucleotide non-coding RNA molecules, have been amongst the most extensively studied. There is evidence to support that miRNA are selectively packaged into EVs and can regulate recipient cell gene expression including major pathways involved in inflammation, apoptosis and fibrosis. Furthermore changes in EV cargo including miRNA have been reported in many chronic diseases and in response to risk factors including respiratory infections, noxious stimuli and ageing. In this review, we discuss the potential of EVs and EV-associated miRNA to modulate shared pathological processes in chronic diseases. Further delineating these may lead to the identification of novel biomarkers and therapeutic targets for patients with COPD and multimorbidities.

Protective effect of Palmijihwanghwan in a mouse model of cigarette smoke and lipopolysaccharide-induced chronic obstructive pulmonary disease

Background

Palmijihwanghwan (PJH) is a traditional medicine and eight constituents derived from PJH possess anti-inflammatory activities. However, the scientific evidence for its potential as a therapeutic agent for inflammatory lung disease has not yet been studied. In this study, we examined the protective effect of PJH in a mouse model of chronic obstructive pulmonary disease (COPD) induced by cigarette smoke (CS) with lipopolysaccharide (LPS).

Methods

Mice received CS exposure for 8 weeks and intranasal instillation of LPS on weeks 1, 3, 5 and 7. PJH (100 and 200 mg/kg) was administrated daily 1 h before CS treatment for the last 4 weeks.

Results

Compared with CS plus LPS-exposed mice, mice in the PJH-treated group showed significantly decreased inflammatory cells count and reduced inflammatory cytokines including interleukin-1 beta (IL-1β), IL-6 and tumor necrosis factor alpha (TNF-α) levels in broncho-alveolar lavage fluid (BALF) and lung tissue. PJH also suppressed the phosphorylation of nuclear factor kappa B (NF-κB) and extracellular signal-regulated kinase1/2 (ERK1/2) caused by CS plus LPS exposure. Furthermore, CS plus LPS induced increases in matrix metallopeptidase (MMP)-7, MMP-9, and transforming growth factor-β (TGF-β) expression and collagen deposition that were inhibited in PJH-treated mice.

Conclusions

This study demonstrates that PJH prevents respiratory inflammation and airway remodeling caused by CS with LPS exposure suggesting potential therapy for the treatment of COPD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-021-03453-5.

Mechanisms, Pathophysiology and Currently Proposed Treatments of Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is one of the leading global causes of morbidity and mortality. A hallmark of COPD is progressive airflow obstruction primarily caused by cigarette smoke (CS). CS exposure causes an imbalance favoring pro- over antioxidants (oxidative stress), leading to transcription factor activation and increased expression of inflammatory mediators and proteases. Different cell types, including macrophages, epithelial cells, neutrophils, and T lymphocytes, contribute to COPD pathophysiology. Alteration in cell functions results in the generation of an oxidative and inflammatory microenvironment, which contributes to disease progression. Current treatments include inhaled corticosteroids and bronchodilator therapy. However, these therapies do not effectively halt disease progression. Due to the complexity of its pathophysiology, and the risk of exacerbating symptoms with existing therapies, other specific and effective treatment options are required. Therapies directly or indirectly targeting the oxidative imbalance may be promising alternatives. This review briefly discusses COPD pathophysiology, and provides an update on the development and clinical testing of novel COPD treatments.

DNA Methylation-Based Age Prediction and Telomere Length Reveal an Accelerated Aging in Induced Sputum Cells Compared to Blood Leukocytes: A Pilot Study in COPD Patients

Aging is the predominant risk factor for most degenerative diseases, including chronic obstructive pulmonary disease (COPD). This process is however very heterogeneous. Defining the biological aging of individual tissues may contribute to better assess this risky process. In this study, we examined the biological age of induced sputum (IS) cells, and peripheral blood leukocytes in the same subject, and compared these to assess whether biological aging of blood leukocytes mirrors that of IS cells. Biological aging was assessed in 18 COPD patients (72.4 ± 7.7 years; 50% males). We explored mitotic and non-mitotic aging pathways, using telomere length (TL) and DNA methylation-based age prediction (DNAmAge) and age acceleration (AgeAcc) (i.e., difference between DNAmAge and chronological age). Data on demographics, life style and occupational exposure, lung function, and clinical and blood parameters were collected. DNAmAge (67.4 ± 5.80 vs. 61.6 ± 5.40 years; p = 0.0003), AgeAcc (-4.5 ± 5.02 vs. -10.8 ± 3.50 years; p = 0.0003), and TL attrition (1.05 ± 0.35 vs. 1.48 ± 0.21 T/S; p = 0.0341) are higher in IS cells than in blood leukocytes in the same patients. Blood leukocytes DNAmAge (r = 0.927245; p = 0.0026) and AgeAcc (r = 0.916445; p = 0.0037), but not TL, highly correlate with that of IS cells. Multiple regression analysis shows that both blood leukocytes DNAmAge and AgeAcc decrease (i.e., younger) in patients with FEV1% enhancement (p = 0.0254 and p = 0.0296) and combined inhaled corticosteroid (ICS) therapy (p = 0.0494 and p = 0.0553). In conclusion, new findings from our work reveal a differential aging in the context of COPD, by a direct quantitative comparison of cell aging in the airway with that in the more accessible peripheral blood leukocytes, providing additional knowledge which could offer a potential translation into the disease management.

Effects of particulate matter gamma radiation on oxidative stress biomarkers in COPD patients

Inhalation of particulate matter (PM) radioactivity is an important pathway of ionizing radiation exposure. We investigated the associations between short-term exposures to PM gamma radioactivity with oxidative stress in COPD patients. Urinary concentrations of 8-hydroxy-2'-deoxyguanosine (8-OHdG) and malondialdehyde (MDA) of 81 COPD patients from Eastern Massachusetts were measured 1-4 times during 2012-2014. Daily ambient and indoor PM gamma activities (gamma-3 through gamma-9) were calculated based on EPA RadNet data and indoor-outdoor infiltration ratios. Linear mixed-effects models were used to examine the associations between biomarkers with PM gamma activities for moving averages from urine collection day to 7 days before. Our results indicate that ambient and indoor PM gamma activities were positively associated with 8-OHdG, with stronger effects for exposure windows closer to urine collection day. For per interquartile range increase in indoor PM gamma activities averaged over urine collection day and 1 day before, 8-OHdG increased from 3.41% (95% CI: -0.88, 7.88) to 8.87% (95% CI: 2.98, 15.1), adjusted for indoor black carbon. For MDA, the timing of greatest effects across the exposure week varied but was nearly all positive. These findings provide insight into the toxigenic properties associated with PM radioactivity and suggest that these exposures promote systemic oxidative stress.

SUL-151 Decreases Airway Neutrophilia as a Prophylactic and Therapeutic Treatment in Mice after Cigarette Smoke Exposure

Chronic obstructive pulmonary disease (COPD) caused by cigarette smoke (CS) is featured by oxidative stress and chronic inflammation. Due to the poor efficacy of standard glucocorticoid therapy, new treatments are required. Here, we investigated whether the novel compound SUL-151 with mitoprotective properties can be used as a prophylactic and therapeutic treatment in a murine CS-induced inflammation model. SUL-151 (4 mg/kg), budesonide (500 μg/kg), or vehicle were administered via oropharyngeal instillation in this prophylactic and therapeutic treatment setting. The number of immune cells was determined in the bronchoalveolar lavage fluid (BALF). Oxidative stress response, mitochondrial adenosine triphosphate (ATP) production, and mitophagy-related proteins were measured in lung homogenates. SUL-151 significantly decreased more than 70% and 50% of CS-induced neutrophils in BALF after prophylactic and therapeutic administration, while budesonide showed no significant reduction in neutrophils. Moreover, SUL-151 prevented the CS-induced decrease in ATP and mitochondrial mtDNA and an increase in putative protein kinase 1 expression in the lung homogenates. The concentration of SUL-151 was significantly correlated with malondialdehyde level and radical scavenging activity in the lungs. SUL-151 inhibited the increased pulmonary inflammation and mitochondrial dysfunction in this CS-induced inflammation model, which implied that SUL-151 might be a promising candidate for COPD treatment.

Effect of periodontal therapy on COPD outcomes: a systematic review

Background

Latest evidence suggests that periodontitis is prevalent among patients with chronic obstructive pulmonary disease (COPD), while recent studies have also reported a potential benefit of periodontal treatment on several COPD outcomes. This systematic review aims to determine the impact of periodontal treatment on exacerbation rate, lung function and quality of life of COPD patients.

Methods

A systematic search of electronic databases of PubMed, Scopus, Virtual Health Library, ScienceDirect, Wiley Online Library, Web of Science, ProQuest Dissertation and Theses Global and Google Scholar was conducted. Search restricted to studies involving human subjects which were published from January 2000 to March 2020 in English language. Distiller Systematic Review software was used for data management. Risk of bias was assessed using Risk of Bias 2 (RoB2) and Risk of Bias for non-randomized studies of intervention (ROBINS-I) tools. Overall quality of evidence was judged based on Grading of Recommendations Assessment, Development and Evaluation working group methodology.

Results

Out of 1442 articles retrieved, 7 full text articles were included in the review. Limited evidence suggests that periodontal treatment in patients with COPD and periodontitis is associated with reduced exacerbation frequency and a slower lung function decline rate, while its effects on quality of life remain unclear. In addition, periodontal treatment in COPD is associated with lower hospitalization rates and reduced all-cause mortality. Significant methodological differences were noted amongst included studies, while very low-to-moderate overall quality of evidence was demonstrated.

Conclusions

Although it is reasonable to advise COPD patients not to neglect their dental health, further studies are warranted to determine the role of periodontal therapy on COPD clinical outcomes.

Trial Registration: PROSPERO 2020 (CRD42020158481). https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020158481

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01429-2.

Fractional heat shock protein 27 urine excretion as a short-term predictor in acute exacerbation of chronic obstructive pulmonary disease

Background

Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality and is characterized by episodes of acute exacerbations. Finding a systemic biomarker that reliably predicts outcome after an acute exacerbation remains a major challenge. Heat shock protein 27 (HSP27) has been previously studied in COPD, however, urine excretion trajectory and prognostic value after an exacerbation is unknown.

Methods

In this retrospective post hoc analysis of a prospective study that included 253 COPD patients who were hospitalized for acute exacerbation, 207 patients were analyzed. Urine and serum were sampled at admission, discharge, and 180 days after discharge; urine excretion trajectory was analyzed and correlated with clinicopathological and survival data.

Results

HSP27 urine excretion increased after an exacerbation episode [1.8% admission, 1.8% discharge, 2.3% 180 days after discharge (P=0.091)]. In severely ill patients (GOLD IV) this course was even more distinct [1.6% admission, 2.1% discharge, 2.8% 180 days after discharge (P=0.007)]. Furthermore, fractional HSP27 urine excretion at discharge was increased in GOLD IV patients (P=0.031). In Kaplan-Meier and univariable Cox proportional hazard models patients with HSP27 urine excretion below 0.845% showed significantly worse survival at 30, 90 and 180 days after discharge. In a multivariable Cox proportional hazard model including established COPD outcome parameters fractional HSP27 urine excretion remained a significant predictor of survival at 30 and 90 days after discharge. Comparing this model to our already published model that includes HSP27 serum concentration we could show that fractional HSP27 urine excretion performs better in short-term survival.

Conclusions

Our findings provide novel information about fractional HSP27 urine excretion trajectory in acute exacerbation of COPD. Fractional HSP27 urine excretion may be significantly reduced during an episode of acute exacerbation in COPD patients and may be used as a predictor of short-term all-cause mortality.

Cigarette smoke affects ESCRT-mediated vacuolar activity in Saccharomyces cerevisiae

Cigarette smoking is a risk factor for developing chronic obstructive pulmonary disease and protein aggresome formation is considered to be a hallmark event for the disease. Since dysfunction of lysosome-mediated protein degradation leads to enhanced accumulation of misfolded proteins and subsequent aggresome formation, we examined the effect of cigarette smoke extract (CSE) on ESCRT-mediated sorting in S. cerevisiae as this process is necessary for the functioning of the vacuole, the lysosomal equivalent in yeast. An operational ESCRT pathway is essential for ion homeostasis and our observation that exposure to CSE caused increased sensitivity to LiCl indicated CSE-induced impairment of ESCRT function. To confirm the inhibition of ESCRT function, the targeting of carboxypeptidase S (CPS), which reaches the vacuole lumen via the ESCRT pathway, was examined. Treatment with CSE resulted in the mislocalization of GFP-tagged CPS to the vacuolar membrane, instead of the vacuolar lumen, confirming defective functioning of the ESCRT machinery in CSE-treated cells. Further analysis revealed that CSE-treatment inhibited the recruitment of the ESCRT-0 component, Vps27, to the endosome surface, which is a key event is for the functioning of the ESCRT pathway. This lack of endosomal recruitment of Vps27 most likely results from a depletion of the endosomally-enriched lipid, phosphatidylinositol 3-phosphate (PI3-P), which is the target of Vps27. This is supported by our observation that the presence of excess leucine, a known activator of the lipid kinase responsible for the generation of PI3-P, Vps34, in the medium can rescue the CSE-induced ESCRT misfunctioning. Thus, the current study provides an insight into CSE-induced aggresome formation as it documents that CSE treatment compromises vacuolar degradation due to an impairment of the ESCRT pathway, which likely stems from the inhibition of Vps34. It also indicates that leucine has the potential to attenuate the CSE-induced accumulation of misfolded proteins.

Cigarillos Compromise the Mucosal Barrier and Protein Expression in Airway Epithelia

Smoking remains a leading cause of preventable morbidity and mortality worldwide. Despite a downward trend in cigarette use, less-regulated tobacco products, such as cigarillos, which are often flavored to appeal to specific demographics, such as younger people, are becoming increasingly popular. Cigar/cigarillo smoking has been considered a safer alternative to cigarettes; however, the health risks associated with cigar in comparison with cigarette smoking are not well understood. To address this knowledge gap, we characterized the effects of multiple brands of cigarillos on the airway epithelium using ex vivo and in vivo models. To analyze these effects, we assessed the cellular viability and integrity of smoke-exposed primary airway cell cultures. We also investigated the protein compositions of apical secretions from cigarillo-exposed airway epithelial cultures and BAL fluid of cigarillo-exposed mice through label-free quantitative proteomics and determined the chemical composition of smoke collected from the investigated cigarillo products. We found that cigarillo smoke exerts similar or greater effects than cigarette smoke in terms of reduced cell viability; altered protein levels, including those of innate immune proteins; induced oxidative-stress markers; and greater nicotine delivery to cells. The analysis of the chemical composition of the investigated cigarillo products revealed differences that might be linked to the differential effects of these products on cell viability and protein abundance profiles, which have been associated with a range of health risks in the context of airway biology. These findings contradict the assumption that cigarillos might be safer and less harmful than cigarettes. Instead, our results indicate that cigarillo smoke is associated with equal or greater health risks and the same or increased airway toxicity compared with cigarette smoke.

Mechanism of Action of Bu-Fei-Yi-Shen Formula in Treating Chronic Obstructive Pulmonary Disease Based on Network Pharmacology Analysis and Molecular Docking Validation

Objective

To explore the mechanism of action of Bu-Fei-Yi-Shen formula (BFYSF) in treating chronic obstructive pulmonary disease (COPD) based on network pharmacology analysis and molecular docking validation.

Methods

First of all, the pharmacologically active ingredients and corresponding targets in BFYSF were mined by the Traditional Chinese Medicine Systems Pharmacology (TCMSP) database, the analysis platform, and literature review. Subsequently, the COPD-related targets (including the pathogenic targets and known therapeutic targets) were identified through the TTD, CTD, DisGeNet, and GeneCards databases. Thereafter, Cytoscape was employed to construct the candidate component-target network of BFYSF in the treatment of COPD. Moreover, the cytoHubba plug-in was utilized to calculate the topological parameters of nodes in the network; then, the core components and core targets of BFYSF in the treatment of COPD were extracted according to the degree value (greater than or equal to the median degree values for all nodes in the network) to construct the core network. Further, the Autodock vina software was adopted for molecular docking study on the core active ingredients and core targets, so as to verify the above-mentioned network pharmacology analysis results. Finally, the Omicshare database was applied in enrichment analysis of the biological functions of core targets and the involved signaling pathways.

Results

In the core component-target network of BFYSF in treating COPD, there were 30 active ingredients and 37 core targets. Enrichment analysis suggested that these 37 core targets were mainly involved in the regulation of biological functions, such as response to biological and chemical stimuli, multiple cellular life processes, immunity, and metabolism. Besides, multiple pathways, including IL-17, Toll-like receptor (TLR), TNF, and HIF-1, played certain roles in the effect of BFYSF on treating COPD.

Conclusion

BFYSF can treat COPD through the multicomponent, multitarget, and multipathway synergistic network, which provides basic data for intensively exploring the mechanism of action of BFYSF in treating COPD.

Metabolic Syndrome and Abnormal Peri-Organ or Intra-Organ Fat (APIFat) Deposition in Chronic Obstructive Pulmonary Disease: An Overview

Chronic obstructive pulmonary disease (COPD) is a common disorder with an increasing prevalence, characterised by persistent respiratory symptoms and airflow limitation. Systemic inflammation is involved in the pathogenesis of COPD and can also predispose to metabolic disorders (e.g., metabolic syndrome (MetS) and non-alcoholic fatty liver disease (NAFLD)). Such comorbidities can negatively affect COPD outcomes, cardiovascular risk, and quality of life. Apart from NAFLD, abnormal peri-organ or intra-organ fat (APIFat) could be considered as markers for cardiometabolic diseases and even for COPD. The present narrative review considers the associations of COPD with MetS, NAFLD, and other APIFat, including epicardial, perirenal, peripancreatic, and intramuscular adipose tissue. Further research is needed to define these relationships and identify any potential clinical implications.

Progress in the mechanism and targeted drug therapy for COPD

Chronic obstructive pulmonary disease (COPD) is emphysema and/or chronic bronchitis characterised by long-term breathing problems and poor airflow. The prevalence of COPD has increased over the last decade and the drugs most commonly used to treat it, such as glucocorticoids and bronchodilators, have significant therapeutic effects; however, they also cause side effects, including infection and immunosuppression. Here we reviewed the pathogenesis and progression of COPD and elaborated on the effects and mechanisms of newly developed molecular targeted COPD therapeutic drugs. Among these new drugs, we focussed on thioredoxin (Trx). Trx effectively prevents the progression of COPD by regulating redox status and protease/anti-protease balance, blocking the NF-κB and MAPK signalling pathways, suppressing the activation and migration of inflammatory cells and the production of cytokines, inhibiting the synthesis and the activation of adhesion factors and growth factors, and controlling the cAMP-PKA and PI3K/Akt signalling pathways. The mechanism by which Trx affects COPD is different from glucocorticoid-based mechanisms which regulate the inflammatory reaction in association with suppressing immune responses. In addition, Trx also improves the insensitivity of COPD to steroids by inhibiting the production and internalisation of macrophage migration inhibitory factor (MIF). Taken together, these findings suggest that Trx may be the ideal drug for treating COPD.

Conventional and Nanotechnology Based Approaches to Combat Chronic Obstructive Pulmonary Disease: Implications for Chronic Airway Diseases

Chronic obstructive pulmonary disease (COPD) is the most prevalent obstructive lung disease worldwide characterized by decline in lung function. It is associated with airway obstruction, oxidative stress, chronic inflammation, mucus hypersecretion, and enhanced autophagy and cellular senescence. Cigarette smoke being the major risk factor, other secondary risk factors such as the exposure to air pollutants, occupational exposure to gases and fumes in developing countries, also contribute to the pathogenesis of COPD. Conventional therapeutic strategies of COPD are based on anti-oxidant and anti-inflammatory drugs. However, traditional anti-oxidant pharmacological therapies are commonly used to alleviate the impact of COPD as they have many associated repercussions such as low diffusion rate and inappropriate drug pharmacokinetics. Recent advances in nanotechnology and stem cell research have shed new light on the current treatment of chronic airway disease. This review is focused on some of the anti-oxidant therapies currently used in the treatment and management of COPD with more emphasis on the recent advances in nanotechnology-based therapeutics including stem cell and gene therapy approaches for the treatment of chronic airway disease such as COPD and asthma.

Metabolic Syndrome in Patients with Coexistent Obstructive Sleep Apnea Syndrome and Chronic Obstructive Pulmonary Disease (Overlap Syndrome)

Background: Evidence suggests that metabolic syndrome (MetS) is highly prevalent in patients with obstructive sleep apnea syndrome (OSAS) and chronic obstructive pulmonary disease (COPD). However, data on the prevalence of MetS in patients having both OSAS and COPD, or overlap syndrome (OS), are scarce. The aim of this study was to evaluate the prevalence and identify predictors of MetS in patients with OS. Methods: MetS was evaluated in consecutive patients who were diagnosed with OS by polysomnography and pulmonary function testing. Results: A total of 163 subjects (138 males and 25 females) were included. MetS was present in 38% of OS patients. Patients were divided into group A (OS without MetS group: 101 patients) and group B (OS with MetS group: 62 patients). Groups were similar in terms of pulmonary function and sleep parameters. In group B, abdominal obesity was the most prevalent component of MetS (100%), followed by hypertension (82.3%), hypertriglyceridemia (72.6%), and hyperglycemia (51.6%). Age (P = 0.009) and body mass index (P = 0.029) were independent predictors of MetS in patients with OS. Conclusions: An increased prevalence of MetS was observed in a group of patients with OS. Early identification and treatment of MetS may play a significant role in prevention of complications related to OS.

Phenolic Composition of the Leaves of Pyrola rotundifolia L. and Their Antioxidant and Cytotoxic Activity

The leaves of Pyrola rotundifolia L. were extracted in the mixed solvent of methanol/acetone/water (2:2:1, v/v/v) and investigated for their phytochemical analysis and biological activity. Total phenolic and flavonoid contents were determined spectrophotometrically. A high content of phenols (208.35 mg GAE/g of dry extract), flavonoids (38.90 mg QE/g of dry extract) and gallotannins (722.91 GAE/g of dry extract) was obtained. Ultra-high performance liquid chromatography diode array detector tandem mass spectrometry (UHPLC-DAD-MS) allowed for the detection of 23 major peaks at 254 nm. The extract was analyzed for its antioxidant capacity using 2,2-diphenyl-1-picryl-hydrazyl (DPPH^•) and 2,2'-azinobis[3-ethylbenzthiazoline]-6-sulfonic acid (ABTS^•+) radical scavenging, metal chelating power and β-carotene-linoleic acid bleaching assays. The examined extract showed moderate radical scavenging and chelating activity, and good inhibiting ability of linoleic acid oxidation (EC₅₀ = 0.05 mg/mL) in comparison to standards. The cytotoxic effect in increasing concentration on five types of leukemic cell lines was also investigated using trypan blue vital staining. It was found that the analyzed extract induced the apoptosis of all the tested cell lines. Our findings suggest that the leaves of P. rotundifolia are a source of valuable compounds providing protection against oxidative damage, hence their use in traditional medicine is justified.

Anti-Allergic and Anti-Inflammatory Effects and Molecular Mechanisms of Thioredoxin on Respiratory System Diseases

Significance: The pathogenesis and progression of allergic inflammation in the respiratory system are closely linked to oxidative stress. Thioredoxin (TRX) is an essential redox balance regulator in organisms and is induced by various oxidative stress factors, including ultraviolet rays, radiation, oxidation, viral infections, ischemia reperfusion, and anticancer agents. Recent Advances: We demonstrated that systemic administration and transgenic overexpression of TRX is useful in a wide variety of in vivo inflammatory respiratory diseases models, such as viral pneumonia, interstitial lung disease, chronic obstructive pulmonary disease, asthma, acute respiratory distress syndrome, and obstructive sleep apnea syndrome, by removing reactive oxygen species, blocking production of inflammatory cytokines, inhibiting migration and activation of neutrophils and eosinophils, and regulating the cellular redox status. In addition, TRX's anti-inflammatory mechanism is different from the mechanisms associated with anti-inflammatory agents, such as glucocorticoids, which regulate the inflammatory reaction in association with suppressing immune responses. Critical Issues: Understanding the molecular mechanism of TRX is very helpful for understanding the role of TRX in respiratory diseases. In this review, we show the protective effect of TRX in various respiratory diseases. In addition, we discuss its anti-allergic and anti-inflammatory molecular mechanism in detail. Future Directions: The application of TRX may be useful for treating respiratory allergic inflammatory disorders. Antioxid. Redox Signal. 32, 785-801.

Anti-oxidative effect of the tyrosine kinase inhibitor nintedanib: a potential therapy for chronic lung allograft dysfunction?

Background: The long-term survival after lung transplantation (LTx) is often limited by the development of chronic lung allograft dysfunction (CLAD). Increased oxidative stress has been found to occur in chronic lung allograft dysfunction because of several risk factors, e.g. immunological factors or drug related factors. The aim of this study was to investigate the anti-oxidative effect of the receptor tyrosine kinase (RTK) inhibitor nintedanib on immunologically induced oxidative stress and on drug induced oxidative stress.Methods: In-vivo studies were used for investigation of immunologically induced oxidative stress: Immunohistochemistry of transglutaminase-2 (TGM-2) was used to figure out a potential anti-oxidative effect of receptor tyrosine kinase inhibitor nintedanib in a rat model of allogeneic left LTx. In-vitro studies were used for investigation of drug induced oxidative stress: Cell viability assay, 2'7'-dichlorodihydrofluorescein diacetate (DCFDA) and immunofluorescence of transglutaminase-2 were disposed to examine the potential impact of nintedanib on cyclosporin A (CsA) treated lung fibroblasts of the rat.Results: In-vivo studies: Allogeneic transplanted animals without drug interaction showed severe chronic rejection and an excessive expression of TGM-2, whereas the application of nintedanib significantly decreased the number of TGM-2 positive cells. In-vitro studies: Concentrations of CsA ranging from 250 ng/ml to 500 ng/ml demonstrated oxidative stress caused by an increased production of reactive oxygen species (ROS) and an overexpression of TGM-2 without inducing apoptosis in cells. Concentrations of more than 1000 ng/ml led to a considerable decrease of cellularity. 30 min-pre-incubation with nintedanib at a concentration between 25 and 100 nM reduced generation of intracellular ROS and expression of TGM-2.Conclusion: These results demonstrate a downregulation of ROS and TGM-2 by pretreatment with the receptor tyrosine kinase inhibitor nintedanib and present its potential anti-oxidative and immunomodulatory effect in the treatment of chronic lung allograft dysfunction.

The influence of weather and climate on patients with respiratory diseases in Vladivostok as a global health implication

PURPOSE

To identify the formation of meteopathic reactions in patients with respiratory diseases under the influence of extreme weather changes in Vladivostok.

METHODS

The short-term meteopathic reaction in patients with respiratory diseases to the impact of "Weather Complex", consisting of nine weather parameters, on the day of patient's examination and on 1 and 2 days before the examination, was assessed. 146 acclimatized residents of Vladivostok (29 patients with chronic bronchitis, 51 patients with controlled asthma, 39 patients with uncontrolled asthma and 27 healthy volunteers) were examined. Pulmonary function (PF) was studied by spirography and by body plethysmography.

RESULTS

The adaptive-compensatory response of PF in patients with respiratory diseases to weather decreases depending on the disease severity, resulting in the development of meteodependence. The impact of "Weather Complex" on a human body is primarily reflected in PF, and the reaction of metabolic parameters is manifested with a 1-2 days time lag. Glutathione peroxidase and glutathione reductase, key factors in maintaining oxidative cell balance, play the most important role in the formation of a compensatory response to weather. In the light of the global health implication, recommendations are suggested to adjust the treatment of patients with respiratory pathology in specific conditions of abruptly changeable weather.

CONCLUSIONS

The maritime monsoon climate creates an additional strain on both respiratory system and systems that ensure the peroxidation balance worsening bronchopulmonary pathology.

Oxidative Stress in COPD

Numerous studies over the years have shown that oxidative stress plays a major role in the development of the disease. Oxidative stress involvement in COPD opens up the possibility of using antioxidant therapies in the treatment of the disease. However, so far, these therapies have shown no clinical benefit indicating that more basic research efforts are needed to understand the underlying mechanisms by which oxidative stress leads to the development of COPD.

Gender Difference in Damage-Mediated Signaling Contributes to Pulmonary Arterial Hypertension

Aims: Pulmonary arterial hypertension (PAH) is a progressive lethal disease with a known gender dimorphism. Female patients are more susceptible to PAH, whereas male patients have a lower survival rate. Initial pulmonary vascular damage plays an important role in PAH pathogenesis. Therefore, this study aimed at investigating the role of gender in activation of apoptosis/necrosis-mediated signaling pathways in PAH. Results: The media collected from pulmonary artery endothelial cells (PAECs) that died by necrosis or apoptosis were used to treat naive PAECs. Necrotic cell death stimulated phosphorylation of toll-like receptor 4, accumulation of interleukin 1 beta, and expression of E-selectin in a redox-dependent manner; apoptosis did not induce any of these effects. In the animal model of severe PAH, the necrotic marker, high mobility group box 1 (HMGB1), was visualized in the pulmonary vascular wall of male but not female rats. This vascular necrosis was associated with male-specific redox changes in plasma, activation of the same inflammatory signaling pathway seen in response to necrosis in vitro, and an increased endothelial-leukocyte adhesion in small pulmonary arteries. In PAH patients, gender-specific changes in redox homeostasis correlated with the prognostic marker, B-type natriuretic peptide. Males had also shown elevated circulating levels of HMGB1 and pro-inflammatory changes. Innovation: This study discovered the role of gender in the initiation of damage-associated signaling in PAH and highlights the importance of the gender-specific approach in PAH therapy. Conclusion: In PAH, the necrotic cell death is augmented in male patients compared with female patients. Factors released from necrotic cells could alter redox homeostasis and stimulate inflammatory signaling pathways.

Theranostic nanozyme: Silk fibroin based multifunctional nanocomposites to combat oxidative stress

Multifunctional nanomaterials integrating therapeutic and imaging modalities in one platform have opened a new era in the present therapeutic strategies. In the present study, a multifunctional silk fibroin-based carrier has been designed for the delivery of antioxidant and imaging agents. One-step desolvation method was used to prepare sulforaphane (antioxidant drug) loaded silk fibroin nanoparticles (SFSNPs). These anionic SFSNPs were further coupled with cationic cerium oxide nanoparticles (CeNPs) and PEI passivated carbon dots (CDs) to form self-assembled CeNP-CD@SFSNPs nanocomposites. CDs were synthesized from mulberry leaves (Morus indica) as green source of carbon and bPEI as a passivating agent to get positively charged CDs. The CDs functioned as molecular probes by emitting green fluorescence while the presence of CeNPs augmented the antioxidant potential due to their unique redox property. Time-dependent in vitro release of sulforaphane was fast in acidic pH than under normal physiological conditions. Cytotoxicity studies were performed on L132 normal epithelial lung cell lines and A549 lung cancer cell lines to analyze the toxicity of the nanocomposites. Green fluorescence from the CDs facilitated in fluorescence microscopic imaging and cellular uptake studies. ROS scavenging capability was analyzed by exposing cells to H₂O₂ stress using flow cytometry and DCFH-DA staining. Overall, the synthesized CeNP-CD@SFSNPs nanocomposites efficiently reduced ROS levels by simultaneously enabling imaging of the cells. Thus, this CeNP-CD@SFSNPs nanocomposite could be a potential candidate for simultaneous imaging and drug delivery against oxidative stress.

Cytotoxic and genotoxic effects in mechanics occupationally exposed to diesel engine exhaust

Diesel engine exhaust (DEE), which is the product of diesel combustion, is considered carcinogenic in humans. It comprises toxic gases, polycyclic aromatic hydrocarbons (PAHs) and particulate matter which can reach the pulmonary parenchyma and trigger various diseases, including cancer. The aim of the present study was to evaluate the potential cytotoxic and genotoxic effects of DEE exposure on peripheral blood and buccal epithelial cells in mechanics occupationally exposed to DEE. We recruited 120 exposed mechanics and 100 non-exposed control individuals. Significant differences were observed between the two groups in terms of percentage of tail DNA and damage index (DI) in the alkaline comet assay; levels of biomarkers by cytokinesis-block micronucleus cytome (CBMN-Cyt) assay; frequency of micronucleus (MN), nucleoplasmic bridge (NPB), nuclear bud (NBUD) and apoptotic cells (APOP) and levels of biomarkers for micronucleus, karyorrhexis (KRX), karyolysis (KRL) and condensed chromatin (CC) by the buccal micronucleus cytome (BM-Cyt) assay. A significant and positive correlation was found between the frequency of MN in lymphocytes and buccal cells in the exposed group. Also, there was a significant correlation between age and percentage of tail DNA and DI in the comet assay, APOP and MN in the CBMN-Cyt assay and NBUD and MN in the BM-Cyt assay. Additionally, we found a positive and significant correlation of MN frequency in lymphocytes and buccal cells and age and MN frequency in lymphocytes with the time of service (years). Regarding lifestyle-related factors, a significant correlation was observed between meat and vitamin consumption and NBUD formation on CBMN-Cyt and between meat consumption and MN formation on CBMN-Cyt. Of the BM-Cyt biomarkers, there was a correlation between alcohol consumption and NBUD formation and between binucleated cell (BN), pyknosis (PYC), CC and KRL occurrence and family cancer history. These results are the first data in Colombia on the cytotoxic and genotoxic effects induced by continuous exposure to DEE and thus showed the usefulness of biomarkers of the comet, CBMN-Cyt and BM-Cyt assays for human biomonitoring and evaluation of cancer risk in the exposed populations.

Therapeutic targeting of the NRF2 and KEAP1 partnership in chronic diseases

The transcription factor NF-E2 p45-related factor 2 (NRF2; encoded by NFE2L2) and its principal negative regulator, the E3 ligase adaptor Kelch-like ECH-associated protein 1 (KEAP1), are critical in the maintenance of redox, metabolic and protein homeostasis, as well as the regulation of inflammation. Thus, NRF2 activation provides cytoprotection against numerous pathologies including chronic diseases of the lung and liver; autoimmune, neurodegenerative and metabolic disorders; and cancer initiation. One NRF2 activator has received clinical approval and several electrophilic modifiers of the cysteine-based sensor KEAP1 and inhibitors of its interaction with NRF2 are now in clinical development. However, challenges regarding target specificity, pharmacodynamic properties, efficacy and safety remain.

Compartmentalization of anti-oxidant and anti-inflammatory gene expression in current and former smokers with COPD

BACKGROUND

Patients with chronic obstructive pulmonary disease (COPD) have high oxidative stress associated with the severity of the disease. Nuclear factor erythroid-2 related factor 2 (Nrf2)-directed stress response plays a critical role in the protection of lung cells to oxidative stress by upregulating antioxidant genes in response to tobacco smoke. There is a critical gap in our knowledge about Nrf-2 regulated genes in active smokers and former-smokers with COPD in different cell types from of lungs and surrogate peripheral tissues.

METHODS

We compared the expression of Nrf2 and six of its target genes in alveolar macrophages, nasal, and bronchial epithelium and peripheral blood mononuclear cells (PBMCs) in current and former smokers with COPD. We compared cell-type specific of Nrf2 and its target genes as well as markers of oxidative and inflammatory stress.

RESULTS

We enrolled 89 patients; expression all Nrf2 target gene measured were significantly higher in the bronchial epithelium from smokers compared to non-smokers. None were elevated in alveolar macrophages and only one was elevated in each of the other compartments.

CONCLUSION

Bronchial epithelium is the most responsive tissue for transcriptional activation of Nrf2 target genes in active smokers compared to former-smokers with COPD that correlated with oxidative stress and inflammatory markers. There were no consistent trends in gene expression in other cell types tested.

TRIAL REGISTRATION

Clinicaltrials.gov : NCT01335971.

Gene silencing of receptor-interacting protein 2 protects against cigarette smoke-induced acute lung injury

BACKGROUND AND PURPOSE

Chronic obstructive pulmonary disease (COPD) is characterized by progressive alveolar damage and generally irreversible airflow limitation. Nuclear factor-κB (NF-κB) plays a critical role in COPD pathogenesis. Receptor-interacting protein 2 (Rip2), a 60 kDa adaptor protein, is a positive regulator of NF-κB pathway and also an inducible transcriptional product of NF-κB activation. We sought to investigate if Rip2 gene silencing could protect against cigarette smoke (CS)-induced acute lung injury.

EXPERIMENTAL APPROACH

Gene silencing efficacy of Rip2 siRNA was characterized in mouse macrophage and mouse lung epithelial cell lines, and in a CS-induced acute lung injury mouse model. Bronchoalveolar lavage (BAL) fluid cell counts, levels of pro-inflammatory and oxidative damage markers, lung section inflammatory and epithelium thickness scorings, and nuclear NF-κB translocation were measured.

KEY RESULTS

CS was found to upregulate Rip2 level in mouse lungs. Rip2 siRNA was able to suppress Rip2 levels in both macrophage and lung epithelial cell lines and in mouse lungs, block CS extract (CSE)-induced mediator release by the cultured cells, and abate neutrophil counts in BAL fluid from CS-challenged mice. Rip2 siRNA suppressed CS-induced inflammatory and oxidative damage markers, and nuclear p65 accumulation and transcriptional activation in lung tissues. Besides, Rip2 siRNA was able to disrupt CSE-induced NF-κB activation in a NF-κB reporter gene assay.

CONCLUSIONS AND IMPLICATIONS

Taken together, we report for the first time that Rip2 gene silencing ameliorated CS-induced acute lung injury probably via disruption of the NF-κB activity, postulating that Rip2 may be a novel therapeutic target for COPD.

ATRA reduces inflammation and improves alveolar epithelium regeneration in emphysematous rat lung

INTRODUCTION

Pulmonary emphysema characterized by alveolar wall destruction is resultant of persistent chronic inflammation. All-trans retinoic acid (ATRA) has been reported to reverse elastase-induced emphysema in rats. However, the underlying molecular mechanisms are so far unknown.

OBJECTIVE

To investigate the therapeutic potential effect of ATRA via the amelioration of the ERK/JAK-STAT pathways in the lungs of emphysematous rats.

METHODS

In silico analysis was done to find the binding efficiency of ATRA with receptor and ligands of ERK & JAK-STAT pathway. Emphysema was induced by porcine pancreatic elastase in Sprague-Dawley rats and ATRA was supplemented as therapy. Lungs were harvested for histopathological, genomics and proteomics analysis.

RESULTS AND DISCUSSION

In silico docking, analysis confirms that ATRA interferes with the normal binding of ligands (TNF-α, IL6ST) and receptors (TNFR1, IL6) of ERK/JAK-STAT pathways respectively. ATRA restored the histology, proteases/antiproteases balance, levels of inflammatory markers, antioxidants, expression of candidate genes of ERK and JAK-STAT pathways in the therapy group.

CONCLUSION

ATRA ameliorates ERK/JAK-STAT pathway in emphysema condition, resulting in alveolar epithelium regeneration. Hence, ATRA may prove to be a potential drug in the treatment of emphysema.

Urban air pollution and climate change: "The Decalogue: Allergy Safe Tree" for allergic and respiratory diseases care

BACKGROUND

According to the World Health Organization, air pollution is closely associated with climate change and, in particular, with global warming. In addition to melting of ice and snow, rising sea level, and flooding of coastal areas, global warming is leading to a tropicalization of temperate marine ecosystems. Moreover, the effects of air pollution on airway and lung diseases are well documented as reported by the World Allergy Organization.

METHODS

Scientific literature was searched for studies investigating the effect of the interaction between air pollution and climate change on allergic and respiratory diseases.

RESULTS

Since 1990s, a multitude of articles and reviews have been published on this topic, with many studies confirming that the warming of our planet is caused by the "greenhouse effect" as a result of increased emission of "greenhouse" gases. Air pollution is also closely linked to global warming: the emission of hydrocarbon combustion products leads to increased concentrations of biological allergens such as pollens, generating a mixture of these particles called particulate matter (PM). The concept is that global warming is linked to the emission of hydrocarbon combustion products, since both carbon dioxide and heat increase pollen emission into the atmosphere, and all these particles make up PM10. However, the understanding of the mechanisms by which PM affects human health is still limited. Therefore, several studies are trying to determine the causes of global warming. There is also evidence that increased concentrations of air pollutants and pollens can activate inflammatory mediators in the airways. Our Task Force has prepared a Decalogue of rules addressing public administrators, which aims to limit the amount of allergenic pollen in the air without sacrificing public green areas.

CONCLUSIONS

Several studies underscore the significant risks of global warming on human health due to increasing levels of air pollution. The impact of climate change on respiratory diseases appears well documented. The last decades have seen a rise in the concentrations of pollens and pollutants in the air. This rise parallels the increase in the number of people presenting with allergic symptoms (e.g., allergic rhinitis, conjunctivitis, and asthma), who often require emergency medical care. Our hope is that scientists from different disciplines will work together with institutions, pharmaceutical companies and lay organizations to limit the adverse health effects of air pollution and global warming.

Nucleosides isolated from Ophiocordyceps sinensis inhibit cigarette smoke extract-induced inflammation via the SIRT1-nuclear factor-κB/p65 pathway in RAW264.7 macrophages and in COPD mice

Background

Ophiocordyceps sinensis (C. sinensis) extracts have been found to have a therapeutic effect on patients with chronic obstructive pulmonary disease (COPD). Silent information regulator 1 (SIRT1) plays an important role in the regulation of inflammatory mediators and correlates with lung function and COPD exacerbations. The objective of this work was to explore the anti-inflammatory effect and preliminary pathways of nucleosides from cultured C. sinensis on RAW264.7 macrophages and COPD mice.

Materials and methods

The nucleosides were extracted from cultured C. sinensis powder and further purified by macroporous resin D101 and glucan G10 columns. Inflammation and oxidative stress models in RAW264.7 macrophages and in mice were established by injection of cigarette smoke extract (CSE). We then examined how the isolated nucleosides regulated the production of the associated inflammatory mediators in vitro and in vivo by enzyme-linked immunosorbent assay, reverse transcription polymerase chain reaction, and Western blot.

Results

The nucleosides inhibited inflammatory mediator expression of tumor necrosis factor-α, interleukin-6, interleukin-1β, and nitric oxide in both the CSE-stimulated RAW264.7 macrophages and mice. Moreover, the nucleosides elevated SIRT1 activation and suppressed nuclear factor-κB (NF-κB)/p65 activation in vitro and in vivo. Nucleoside treatment significantly decreased the levels of the inflammatory mediators in the bronchoalveolar lavage fluid (BALF) and serum of the CSE-induced mice. The nucleosides also altered the recruitment of inflammatory cells in BALF and improved characteristic features of the lungs in the CSE-induced mice.

Conclusion

These results show that the nucleosides suppressed COPD inflammation through the SIRT1–NF-κB/p65 pathway, suggesting that the nucleosides may be partly responsible for the therapeutic effects of cultured C. sinensis on COPD patients.

Ribosomal Protein S3 Gene Silencing Protects Against Cigarette Smoke-Induced Acute Lung Injury

Chronic obstructive pulmonary disease (COPD) is estimated to be the third leading cause of death by 2030. Transcription factor NF-κB may play a critical role in COPD pathogenesis. Ribosomal protein S3 (RPS3), a 40S ribosomal protein essential for executing protein translation, has recently been found to interact with the NF-κB p65 subunit and promote p65 DNA-binding activity. We sought to study whether RPS3 gene silencing could protect against cigarette-smoke (CS)-induced acute lung injury in a mouse model. Effects of an intratracheal RPS3 siRNA in CS-induced lung injury were determined by measuring bronchoalveolar lavage (BAL) fluid cell counts, levels of inflammatory and oxidative damage markers, and NF-κB translocation. Lung RPS3 level was found to be upregulated for the first time with CS exposure, and RPS3 siRNA blocked CS-induced neutrophil counts in BAL fluid. RPS3 siRNA suppressed CS-induced lung inflammatory mediator and oxidative damage marker levels, as well as nuclear p65 accumulation and transcriptional activation. RPS3 siRNA was able to disrupt CS extract (CSE)-induced NF-κB activation in an NF-κB reporter gene assay. We report for the first time that RPS3 gene silencing ameliorated CS-induced acute lung injury, probably via interruption of the NF-κB activity, postulating that RPS3 is a novel therapeutic target for COPD.