Oxidative stress in asthma and COPD: antioxidants as a therapeutic strategy

Based exploration of the diagnostic value of oxidative stress-related key genes in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) ranks as the third most common contributor to global mortality. Oxidative stress has been recognized as a critical driver of multiple interacting mechanisms in COPD development. This research investigated the potential of oxidative stress-related genes (OSRGs) biomarkers and their potential molecular mechanisms for COPD clinical diagnosis and treatment through bioinformatics analyses. As a result, 5 hub genes, CA3, PPP1R15B, MAPT, MMP9, and ECT2, were yielded by LASSO, Boruta, and SVM-RFE, and the performance of the nomogram constructed based on hub genes was favorable. Correlation analyses between hub genes and oxidative stress biomarkers showed that MMP9 and MAPT genes had a high association with oxidative stress biomarkers. Immune cell infiltration identified follicular helper T cells, Γδ T cells, M0 macrophages, and CD8 T cells as significantly different in COPD. ROC of ECT2 and MMP9 showed a higher capability to discriminate COPD patients from normal samples. In addition, we collected clinical samples and analyzed the core gene expression, which revealed that the hub genes ECT2 and MMP9 had high discriminatory ability in the COPD samples. The epistasis of ECT2 and MMP9 was further verified by constructing animal models, pathological sections, qPCR, immunoblotting, immunohistochemistry, etc. The data indicated the crucial function of MMP9 in CSC-induced oxidative stress injury. Deprivation of MMP9 attenuated CSC-induced injury and promoted macrophage polarisation to M2 macrophages. MMP9 deprivation protected against CSC-induced injury, mainly related to the reduction of cell apoptosis, cell inflammation, and ROS injury in BEAS-2B. It promoted macrophage polarization from M1 to M2. In summary, we found ECT2 and MMP9 are related to oxidative stress in COPD, and MMP9 was related to cell apoptosis, cell inflammation, and ROS injury in BEAS-2B, and the macrophage polarization from M1 to M2.

Relationships between oxidative balance score and asthma, COPD, with asthma-COPD overlap in American adults: findings from NHANES 2013-2018

BACKGROUND

Oxidative stress plays a crucial role in the development of multiple chronic respiratory diseases. Oxidative Balance Score (OBS) composing of 16 dietary factors and 4 lifestyle factors has been developed to evaluate the effect of oxidants/antioxidants produced by dietary intake and lifestyle habits on the overall oxidative balance. However, the relationships between OBS with asthma, COPD, and asthma-COPD overlap (ACO) are still unclear.

METHODS

A total of 10,942 adults aged 20 years and older from the 2013-2018 National Health and Nutrition Examination Survey were included in the analyses. ANOVA and chi-square tests were used to compare characteristics between different OBS subgroups. Multiple multivariate logistic regression was used to analyze the associations between OBS and asthma, COPD, and ACO.RCS curves were used to describe the dose-response effect of the associations. Subgroup analyses and interaction effects were employed to reflect the stability of the associations.

RESULTS

In the fully adjusted models, OBS was found to be negatively associated with asthma, COPD, and ACO. OBS at Q2, Q3, and Q4 (OR: 0.66, 95% CI: 0.46-0.97) were negatively associated with the risk of asthma. OBS at Q2 and Q4 were negatively associated with the risk of COPD. OBS at Q2 and Q4 were negatively associated with the risk of ACO. The RCS curves reflected the negative dose-response trend of association. Moreover, the associations were stable in various subgroups.

CONCLUSION

The negative associations between OBS and asthma, COPD, and ACO were found in American adults, providing evidence for dietary and lifestyle prevention.

Identification of benzo(a)pyrene-related toxicological targets and their role in chronic obstructive pulmonary disease pathogenesis: a comprehensive bioinformatics and machine learning approach

BACKGROUND

Chronic obstructive pulmonary disease (COPD) pathogenesis is influenced by environmental factors, including Benzo(a)pyrene (BaP) exposure. This study aims to identify BaP-related toxicological targets and elucidate their roles in COPD development.

METHODS

A comprehensive bioinformatics approach was employed, including the retrieval of BaP-related targets from the Comparative Toxicogenomics Database (CTD) and Super-PRED database, identification of differentially expressed genes (DEGs) from the GSE76925 dataset, and protein-protein interaction (PPI) network analysis. Functional enrichment and immune infiltration analyses were conducted using GO, KEGG, and ssGSEA algorithms. Feature genes related to BaP exposure were identified using SVM-RFE, Lasso, and RF machine learning methods. A nomogram was constructed and validated for COPD risk prediction. Molecular docking was performed to evaluate the binding affinity of BaP with proteins encoded by the feature genes.

RESULTS

We identified 72 differentially expressed BaP-related toxicological targets in COPD. Functional enrichment analysis highlighted pathways related to oxidative stress and inflammation. Immune infiltration analysis revealed significant increases in B cells, DC, iDC, macrophages, T cells, T helper cells, Tcm, and TFH in COPD patients compared to controls. Correlation analysis showed strong links between oxidative stress, inflammation pathway scores, and the infiltration of immune cells, including aDC, macrophages, T cells, Th1 cells, and Th2 cells. Seven feature genes (ACE, APOE, CDK1, CTNNB1, GATA6, IRF1, SLC1A3) were identified across machine learning methods. A nomogram based on these genes showed high diagnostic accuracy and clinical utility. Molecular docking revealed the highest binding affinity of BaP with CDK1, suggestive of its pivotal role in BaP-induced COPD pathogenesis.

CONCLUSIONS

The study elucidates the molecular mechanisms of BaP-induced COPD, specifically highlighting the role of oxidative stress and inflammation pathways in promoting immune cell infiltration. The identified feature genes may serve as potential biomarkers and therapeutic targets. Additionally, the constructed nomogram demonstrates high accuracy in predicting COPD risk, providing a valuable tool for clinical application in BaP-exposed individuals.

Transcription Factor Blimp-1: A Central Regulator of Oxidative Stress and Metabolic Reprogramming in Chronic Inflammatory Diseases

B-lymphocyte-induced maturation protein 1 (Blimp-1) is a transcription factor that, among other functions, modulates metabolism and helps to regulate antioxidant pathways, which is important in the context of chronic inflammatory diseases like diabetes, cardiovascular disease, and autoimmune disease. In immune cell function, Blimp-1 has a modulatory role in the orchestration of metabolic reprogramming and as a promoter of anti-inflammatory cytokines, including IL-10, responsible for modulating oxidative stress and immune homeostasis. Moreover, Blimp-1 also modulates key metabolic aspects, such as glycolysis and fatty acid oxidation, which regulate reactive oxygen species levels, as well as tissue protection. This review depicts Blimp-1 as an important regulator of antioxidant defenses and anti-inflammation and suggests that the protein could serve as a therapeutic target in chronic inflammatory and metabolic dysregulation conditions. The modulation of Blimp-1 in diseases such as diabetic coronary heart disease and atherosclerosis could alleviate oxidative stress, augment the protection of tissues, and improve disease outcomes. The therapeutic potential for the development of new treatments for these chronic conditions lies in the synergy between the regulation of Blimp-1 and antioxidant therapies, which are future directions that may be pursued. This review emphasizes Blimp-1's emerging importance as a novel regulator in the pathogenesis of inflammatory diseases, providing new opportunities for therapeutic intervention.

Association of life's essential 8 and asthma: mediating effect of inflammation and oxidative stress

BACKGROUND

The association of cardiovascular health (CVH) with asthma risk in U.S. adults remains unclear. This study aimed to explore the association of Life's Essential 8 (LE8), a measurement of CVH, with asthma and investigate the potential mediating effect of inflammation and oxidative stress.

METHODS

The data was obtained from the National Health and Nutrition Examination Survey (NHANES) in 2005-2018. LE8 score (range 0 ∼ 100) was measured and categorized as low (<50), moderate (50 ∼ <80), and high (≥80) CVH. Survey-weighted logistic regression and restricted cubic spline model were employed to explore the association between LE8 score and asthma. Mediation analyses were conducted to identify the mediating effects of inflammation and oxidative stress biomarkers.

RESULTS

This study included 10,932 participants aged ≥ 20 years, among whom 890 (8.14%) reported prevalent asthma. After adjusting for all covariates, the odd ratios (OR) for asthma were 0.67 (95% confidence interval (CI): 0.48, 0.94) in the moderate CVH group and 0.52 (95% CI: 0.34, 0.79) in the high CVH group compared with the low CVH group, respectively. The OR for asthma was 0.85 (95% CI: 0.78, 0.93) for every 10 score increase in LE8 score, and linear dose-response relationship was observed (p = 0.0642). Mediation analyses showed that inflammation and oxidative stress mediated 15.97% and 11.50% of the association between LE8 score and asthma, respectively (all p < 0.05).

CONCLUSIONS

LE8 score was negatively associated with asthma, and inflammation and oxidative stress partially mediated this association. It is recommended that maintaining optimal CVH may prevent asthma.

The interplay of plant-based antioxidants, inflammation, and clinical outcomes in asthma: A systematic review

BACKGROUND

Asthma is a chronic inflammatory disease and a leading cause of disability, posing a huge economic and social burden. Plant-based antioxidants have the potential to block proinflammatory pathways and protect against oxidative damage, which could improve asthma management.

OBJECTIVE

This review examines the role of plant-based antioxidants as adjuvant therapy on inflammatory markers and clinical outcomes of adults with asthma.

METHODS

Digital databases, including Scopus, MEDLINE, EMBASE, CINAHL, PsycINFO, and Cochrane Airway Group's Specialized Register of Trials, were searched. Two independent authors performed initial and full-text screening of identified papers. The criteria for study inclusion and exclusion were predefined. Two authors independently performed data extraction and risk of bias as per the PRISMA checklist.

RESULTS

After full-text screening, nine randomized controlled trials were included in the final review. Seven of the included studies highlighted the efficacy of plant-based antioxidants in modulating the inflammatory cytokines in asthmatics. The benefits of antioxidants were also observed for improving oxidative status, lung functioning, and airway inflammatory markers. Furthermore, the overall quality of asthmatic patients' lives was improved with fewer exacerbations such as night coughs and wheezing. Despite having some limitations, the overall risk of bias was low in this review.

CONCLUSION

The review indicated that plant-based antioxidants could have adjuvant beneficial effects in the management of asthma inflammatory markers, which may help improve asthma-related clinical outcomes. However, due to the small number of study subjects, further research is required on the effect of plant-based antioxidants on asthma-inflammatory markers and clinical outcomes.

The antioxidant barrier, oxidative/nitrosative stress, and protein glycation in allergy: from basic research to clinical practice

Recent studies indicate that oxidative/nitrosative stress is involved in the pathogenesis of asthma, allergic rhinitis, atopic dermatitis, and urticaria. The article aimed to review the latest literature on disruptions in redox homeostasis and protein glycation in allergy patients. It has been shown that enzymatic and non-enzymatic antioxidant systems are impaired in allergic conditions, which increases cell susceptibility to oxidative damage. Reactive oxygen/nitrogen species exacerbate the severity of asthma symptoms by activating inflammatory mediators that cause airway smooth muscle contraction, promote mucus hypersecretion, increase the permeability of lung capillaries, and damage cell membranes. Redox biomarkers could have considerable diagnostic potential in allergy patients. There is no compelling evidence to indicate that antioxidants reduce allergy symptoms' severity or slow disease progression.

The Role of Trace Elements in COPD: Pathogenetic Mechanisms and Therapeutic Potential of Zinc, Iron, Magnesium, Selenium, Manganese, Copper, and Calcium

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a progressive, inflammatory airway disorder characterized by a gradual decline in lung function and increased oxidative stress. Both oxidative stress and inflammation are central to its pathophysiology, with trace elements such as zinc, copper, iron, manganese, magnesium, selenium, and calcium playing key roles in various cellular processes.

OBJECTIVE

This article reviews the role of trace elements in COPD, focusing on their involvement in disease pathogenesis and their therapeutic potential. Specifically, we examine the effects of zinc, copper, iron, magnesium, manganese, selenium, and calcium in COPD.

METHODS

We performed a comprehensive narrative review of the literature across databases including PubMed, Web of Science, Cochrane Library, and Google Scholar, identifying studies that explore the therapeutic effects of trace elements in COPD. The studies included in the review consisted of cohort analyses, randomized controlled trials, and clinical investigations.

RESULTS

Zinc, copper, iron, magnesium, manganese, selenium, and calcium are critical to both the pathophysiology and management of COPD. These trace elements contribute to the regulation of inflammation, the modulation of oxidative stress, and the maintenance of lung function. Zinc and copper, for instance, reduce oxidative stress and modulate immune responses, while iron is essential for oxygen transport. Magnesium, manganese, selenium, and calcium are vital for muscle function, respiratory performance, reducing inflammation, and improving pulmonary function.

CONCLUSIONS

The minerals zinc, copper, iron, magnesium, manganese, selenium, and calcium may contribute to beneficial effects as part of the standard therapeutic management of COPD. Maintaining optimal levels of these trace elements may support the regulation of inflammatory processes, a reduction in oxidative stress, and an improvement in the pulmonary function. However, further clinical research is necessary to confirm their efficacy and establish safe dosage recommendations in COPD treatment.

Epigenetic mechanisms of alveolar macrophage activation in chemical-induced acute lung injury

Airways, alveoli and the pulmonary tissues are the most vulnerable to the external environment including occasional deliberate or accidental exposure to highly toxic chemical gases. However, there are many effective protective mechanisms that maintain the integrity of the pulmonary tissues and preserve lung function. Alveolar macrophages form the first line of defense against any pathogen or chemical/reactant that crosses the airway mucociliary barrier and reaches the alveolar region. Resident alveolar macrophages are activated or circulating monocytes infiltrate the airspace to contribute towards inflammatory or reparative responses. Studies on response of alveolar macrophages to noxious stimuli are rapidly emerging and alveolar macrophage are also being sought as therapeutic target. Here such studies have been reviewed and put together for a better understanding of the role pulmonary macrophages in general and alveolar macrophage in particular play in the pathogenesis of disease caused by chemical induced acute lung injury.

Bidirectional Causal Association Between Chronic Obstructive Pulmonary Disease and Cardiovascular Diseases: A Mendelian Randomization Study

Background

A large number of studies have demonstrated links between chronic obstructive pulmonary disease (COPD) and cardiovascular diseases (CVDs). However, the causal relationship between COPD and CVDs and the reverse causality remains divergent.

Methods

Exposure and outcome data from the largest available genome-wide association studies were extracted for Mendelian randomization (MR) studies. Univariate MR analysis was performed using IVW as the primary analysis method, and multiple sensitivity analyses were used to enhance the robustness of the results. Furthermore, this was followed by mediation MR analysis of positive results after excluding confounding factors with multivariable MR analysis.

Results

The MR estimation based on IVW method indicated a strong association between genetically determined COPD and heart failure (HF) (OR = 1.117, 95% CI: 1.066-1.170, p <0.001), coronary heart disease (CHD) (OR = 1.004, 95% CI: 1.002-1.006, p <0.001), essential hypertension (EH) (OR = 1.009, 95% CI: 1.005-1.013, p <0.001) as well as Stroke (OR = 1.003, 95% CI: 1.001-1.004, p <0.001). The results of multivariable MR analysis revealed that COPD is not significantly associated with CHD after adjusting for IL-6, LDL, or total cholesterol (p>0.05). Our findings indicated that BMI, smoking initiation, smoking status, obesity, and FEV1 played a role in the causal effect of COPD on HF, EH, and Stroke.

Conclusion

We found positive causal relationships between COPD and HF, EH, and Stroke essentially unaffected by other confounding factors. The causal relationship exhibited between COPD and CHD was influenced by confounding factors. BMI, obesity, initiation of smoking, smoking status, and FEV1 were the mediators between COPD and CVDs.

Biochemical characterization of mulberry (Morus spp.) genotypes from the Türkiye (Hizan, Bitlis): A comprehensive analysis of fruit properties and bioactive compounds

The present study was carried out to assess the fruit traits and phytochemical properties of 39 mulberry genotypes [Morus alba L. (16 white mulberry), Morus rubra L. (11 red mulberry), and Morus nigra L. (12 black mulberry)] selected in Bitlis province (Hizan) of Türkiye. Approximately, 1 kg fruit were hand-harvested from each genotype. The fruit size, fruit color, pH, titratable acidity, soluble solids content (SSC), vitamin C, total phenolics, total flavonoids, antioxidant activity, and individual phenolic compounds were determined. The fruit weight varied between 1.80 and 5.84 g in black mulberry, 1.22 and 4.18 g in red mulberry, and 1.29 and 3.10 g in white mulberry. In white mulberry, SSC was determined to be between 19.00% and 38.86%, and in black and red mulberry it was between 11.86% and 21.90% and 12.60% and 18.90%, respectively. The titratable acidity rate, which varied depending on the species, was lower in white mulberry, but the highest acidity rate was recorded in red mulberry. Vitamin C was determined as 33.13 mg 100 g-1 in red mulberry, 24.10 mg 100 g-1 in black mulberry, and 14.03 mg 100 g-1 in white mulberry. Total phenolics in mulberries varied depending on the species, and the red mulberry fruit contained higher phenolic substances, followed by black and white mulberries. The total flavonoids varied between 0.27 and 7.83 g QE kg-1, whereas the flavonoids varied depending on the species and genotype. The highest values in terms of bioactive compounds were recorded in fruits of the 13HZN23 and 37 genotypes. Black and red mulberry fruit were found to have higher levels of individual phenolic content than the white mulberrry fruit.

Novel mycophenolic acid precursor-based fluorescent probe for intracellular H2O2 detection in living cells and Daphnia magna and Zebrafish model systems

Innovative for the scientific community and attracting attention in the extensive biomedical field are novel compact organic chemosensing systems built upon unique core molecular frameworks. These systems may demonstrate customized responses and may be adaptable to analytes, showing promise for potential in vivo applications. Our recent investigation focuses on a precursor of Mycophenolic acid, resulting in the development of LBM (LOD = 13 nM) - a specialized probe selective for H2O2. This paper details the synthesis, characterization, and thorough biological assessments of LBM. Notably, we conducted experiments involving living cells, daphnia, and zebrafish models, utilizing microscopy techniques to determine probe nontoxicity and discern distinct patterns of probe localization. Localization involved the distribution of the probe in the Zebrafish model within the gut, esophagus, and muscles of the antennae.

A Review on in-vivo and in-vitro Models of Obesity and Obesity-Associated Co-Morbidities

BACKGROUND

Obesity is becoming a global pandemic with pandemic proportions. According to the WHO estimates, there were over 1.9 billion overweight individuals and over 650 million obese adults in the globe in 2016. In recent years, scientists have encountered difficulties in choosing acceptable animal models, leading to a multitude of contradicting aspects and incorrect outcomes. This review comprehensively evaluates different screening models of obesity and obesity-associated comorbidities to reveal the advantages and disadvantages/limitations of each model while also mentioning the time duration each model requires to induce obesity.

METHODOLOGY

For this review, the authors have gone through a vast number of article sources from different scientific databases, such as Google Scholar, Web of Science, Medline, and PubMed.

RESULTS

In-vivo models used to represent a variety of obesity-inducing processes, such as diet-induced, drug-induced, surgical, chemical, stress-induced, and genetic models, are discussed. Animal cell models are examined with an emphasis on their use in understanding the molecular causes of obesity, for which we discussed in depth the important cell lines, including 3T3-L1, OP9, 3T3-F442A, and C3H10T1/2. Screening models of obesity-associated co-morbidities like diabetes, asthma, cardiovascular disorders, cancer, and polycystic ovarian syndrome (PCOS) were discussed, which provided light on the complex interactions between obesity and numerous health problems.

CONCLUSION

Mimicking obesity in an animal model reflects multifactorial aspects is a matter of challenge. Future studies could address the ethical issues surrounding the use of animals in obesity research as well as investigate newly developed models, such as non-mammalian models. In conclusion, improving our knowledge and management of obesity and related health problems will require ongoing assessment and improvement of study models.

E-selectin in vascular pathophysiology

Selectins are a group of Ca2+-dependent, transmembrane type I glycoproteins which attract cell adhesion and migration. E-selectin is exclusively expressed in endothelial cells, and its expression is strongly enhanced upon activation by pro-inflammatory cytokines. The interaction of E-selectin with its ligands on circulating leukocytes captures and slows them down, further facilitating integrin activation, firm adhesion to endothelial cells and transmigration to tissues. Oxidative stress induces endothelial cell injury, leading to aberrant expression of E-selectin. In addition, the elevated level of E-selectin is positively related to high risk of inflammation. Dysregulation of E-selectin has been found in several pathological conditions including acute kidney injury (AKI), pulmonary diseases, hepatic pathology, Venous thromboembolism (VTE). Deletion of the E-selectin gene in mice somewhat ameliorates these complications. In this review, we describe the mechanisms regulating E-selectin expression, the interaction of E-selectin with its ligands, the E-selectin physiological and pathophysiological roles, and the therapeutical potential of targeting E-selectin.

Guggulsterone protects against cigarette smoke-induced COPD linked lung inflammation

Recently, we have shown that guggulsterone is the principal constituent responsible for protective effects of Commiphora wightii against elastase-induced chronic obstructive pulmonary disease (COPD)-linked inflammation/emphysema. Given that cigarette smoke (CS) exposure is a primary risk factor for COPD and beneficial effects of guggulsterone have not been investigated in CS-induced COPD-linked lung inflammation. The present work was designed to validate the potential of guggulsterone in amelioration of COPD-linked lung inflammation by using a CS-based mouse model of the condition. Male BALB/c mice were exposed to 9 cigarettes/day with 1 h interval for 4 days daily. Guggulsterone was administered daily at a dose of 10 mg/kg orally for 4 consecutive days, 1 h before initiation of CS exposure. Mice were subjected to measurement of lung function followed by procurement of bronchoalveolar lavage fluid (BALF)/lung tissue. BALF was analyzed for inflammatory cells and pro-inflammatory cytokines. Lung tissue was subjected to RT-PCR for gene expression analysis. Data showed that CS exposure resulted in a significant increase in total BALF cells, predominantly neutrophils, and macrophages. Interestingly, guggulsterone administration significantly blunted CS-induced inflammation as reflected by reduced neutrophil and macrophage count. Further, the compound inhibited CS-induced gene expression of pro-inflammatory mediators TNF-α/ IL-1β/ G-CSF/and KC in lungs along with the production of pro-inflammatory mediators TNF-α/ IL-1β/ IL-6/ G-CSF/ KC/and MCP-1 in BALF. Further, guggulsterone improved the lung function parameters upon CS exposure. Analysis of mRNA expression of matrix metalloproteinase (MMP)-9 and tissue inhibitor of matrix metalloproteinase (TIMP)-1 suggests that guggulsterone may restore the fine balance between matrix-degrading proteases and its inhibitor in lung tissue upon CS exposure, which may contribute in the development of emphysema at later stages. Overall, our data show that guggulsterone protects against CS-induced COPD-linked lung inflammation by modulating relevant molecular players. Based on the potential effects of guggulsterone in the amelioration of CS-induced lung inflammation, we speculate that guggulsterone might alter chronic CS-induced emphysema.

Lipid-Laden Macrophages in Pulmonary Diseases

Pulmonary surfactants play a crucial role in managing lung lipid metabolism, and dysregulation of this process is evident in various lung diseases. Alternations in lipid metabolism lead to pulmonary surfactant damage, resulting in hyperlipidemia in response to lung injury. Lung macrophages are responsible for recycling damaged lipid droplets to maintain lipid homeostasis. The inflammatory response triggered by external stimuli such as cigarette smoke, bleomycin, and bacteria can interfere with this process, resulting in the formation of lipid-laden macrophages (LLMs), also known as foamy macrophages. Recent studies have highlighted the potential significance of LLM formation in a range of pulmonary diseases. Furthermore, growing evidence suggests that LLMs are present in patients suffering from various pulmonary conditions. In this review, we summarize the essential metabolic and signaling pathways driving the LLM formation in chronic obstructive pulmonary disease, pulmonary fibrosis, tuberculosis, and acute lung injury.

Integrated serum metabolomics and network pharmacology analysis on the bioactive metabolites and mechanism exploration of Bufei huoxue capsule on chronic obstructive pulmonary disease rats

ETHNOPHARMACOLOGICAL RELEVANCE

Bufei Huoxue capsule (BHC) as a classic Chinese patent medicine formula, has the efficacy of tonifying the lungs and activating the blood. It has been extensively used in China for the treatment of chronic obstructive pulmonary disease (COPD) clinically. However, its mechanism is still unclear, which hampers the applications of BHC in treating COPD.

AIM OF THE STUDY

The purpose of the present study was to demonstrate the protective efficacy and mechanism of BHC on COPD model rats by integrating serum metabolomics analysis and network pharmacology study.

MATERIALS AND METHODS

A COPD rat model was established by cigarette fumigation combined with lipopolysaccharide (LPS) airway drip for 90 consecutive days. After oral administration for 30 days, the rats were placed in the body tracing box of the EMKA Small Animal Noninvasive Lung Function Test System to determine lung function related indexes. Histopathological alteration was observed by H&E staining and Masson staining. The serum levels of inflammatory cytokine, matrix metalloprotein 9, and laminin were determined by ELISA kits. Oxidative stress levels were tested by biochemical methods. UHPLC-Q-TOF/MS analysis of serum metabolomics and network pharmacology were performed to reveal the bioactive metabolites, key components and pathways for BHC treating COPD. WB and ELISA kits were used to verify the effects of BHC on key pathway.

RESULTS

BHC could improve lung function, immunity, lung histopathological changes and collagen deposition in COPD model rats. It also could significantly reduce inflammatory response in vivo, regulate oxidative stress level, reduce laminin content, and regulate protease-antiprotease balance. Metabolomics analysis found 46 biomarkers of COPD, of which BHC significantly improved the levels of 23 differential metabolites including arachidonic acid, leukotriene B4 and prostaglandin E2. Combined with the results of network pharmacology, the components of BHC, such as calycosin, oxypaeoniflora, (S)-bavachin and neobavaisoflavone could play therapeutic roles through the arachidonic acid pathway. In addition, the results of WB and ELISA indicated that BHC could suppress the expressions of COX2 and 5-LOX in lung tissues and inhibit the generation of AA and its metabolites in serum samples. Regulation of arachidonic acid metabolic pathway may be the crucial mechanism for BHC treating COPD.

CONCLUSIONS

In summary, the studies indicated that BHC exhibited the protective effect on COPD model rats by anti-inflammatory and anti-oxidative properties through arachidonic acid metabolism pathway. This study provided beneficial support for the applications of BHC in treating COPD.

Differences in Airway Remodeling and Emphysematous Lesions between Rats Exposed to Smoke from New-Type and Conventional Tobacco Varieties

Genes from Perilla frutescens and Ocimum basilicum were introduced into N. tabacum L. var. HHY via distant hybridization, and the new-type tobacco varieties "Zisu" and "Luole" were developed, with noticeable differences in chemical composition. Smoking is the leading cause of chronic obstructive pulmonary disease (COPD), and its pathogenesis is complex. In the present study, 48 male Sprague-Dawley (SD) rats were randomly divided into four groups, namely, the control, "HHY", "Zisu" and "Luole", and then exposed to fresh air/cigarette smoke (CS) for 30 days and 60 days. The COPD model was constructed, and their health hazards were compared and evaluated. CS from different tobacco varieties influenced rats in varying degrees at the tissue, cell and molecular levels. The rats in the "HHY" group showed obvious symptoms, such as cough and dyspnea, which were less severe in the "Zisu" and "Luole" groups. Pathological and morphological analyses, including scores, MLI, MAN, WAt/Pbm and WAm/Pbm, showed that "Zisu" and "Luole" caused less damage to the airways and lung parenchyma than "HHY". Significant increases in the numbers of total leukocytes and neutrophils in the BALF were found in "HHY" compared to those in "Zisu" and "Luole". Moreover, they caused less oxidative stress and apoptosis in lung tissues, as reflected by indicators such as ROS, MDA, T-AOC, GSH, the apoptotic index and the ratio of Bcl-2 to Bax. "Zisu" and "Luole" even altered the ratios of MMP-9/TIMP-1 and IFN-γ/IL-4 in lung tissues to a lesser degree. These differences between CS-exposed rats may be closely related to the altered expression of Nrf2, p38 MAPK and p-p38 MAPK. Changes in chemical composition via introducing genes from some medicinal plants may be an attractive strategy for tobacco harm reduction.

Improvement of Lung Function by Micronutrient Supplementation in Patients with COPD: A Systematic Review and Meta-Analysis

BACKGROUND

A healthy, well-balanced diet plays an essential role in respiratory diseases. Since micronutrient deficiency is relatively common in patients with chronic obstructive pulmonary disease (COPD), micronutrient supplementation might have the beneficial health effects in those patients. This systematic review and meta-analysis aimed to demonstrate the impact of micronutrient supplementation on the lung function of patients with COPD.

METHODS

The PubMed, Cochrane Library, and Web of Science databases were searched from their corresponding creation until February 2024. Search terms included 'chronic obstructive pulmonary disease', 'COPD', 'micronutrients', 'dietary supplements', 'vitamins', 'minerals', and 'randomized controlled trials'. Meta-analysis was performed to evaluate the effects of micronutrient supplementation alone or complex on lung function in patients with COPD.

RESULTS

A total of 43 RCTs fulfilled the inclusion criteria of this study. Meta-analysis revealed that vitamin D supplementation could significantly improve FEV1% (WMDdifferences between baseline and post-intervention (de): 6.39, 95% CI: 4.59, 8.18, p < 0.01; WMDpost-intervention indicators (af): 7.55, 95% CI: 5.86, 9.24, p < 0.01) and FEV1/FVC% (WMDde: 6.88, 95%CI: 2.11, 11.65, WMDaf: 7.64, 95% CI: 3.18, 12.10, p < 0.001), decrease the odds of acute exacerbations, and improve the level of T-cell subsets, including CD3+%, CD4+%, CD8+%, and CD4+/CD8+% (all p < 0.01). The effects of compound nutrients intervention were effective in improving FEV1% (WMDde: 8.38, 95%CI: 1.89, 14.87, WMDaf: 7.07, 95%CI: -0.34, 14.48) and FEV1/FVC% (WMDde: 7.58, 95% CI: 4.86, 10.29, WMDaf: 6.00, 95% CI: 3.19, 8.81). However, vitamin C and vitamin E supplementation alone had no significant effects on lung function (p > 0.05).

CONCLUSIONS

Micronutrient supplementation, such as vitamin D alone and compound nutrients, has improved effect on the lung function of patients with COPD. Therefore, proper supplementation with micronutrients would be beneficial to stabilize the condition and restore ventilation function for COPD patients.

A Comparative Study of the Effects of Electronic Cigarette and Traditional Cigarette on the Pulmonary Functions of C57BL/6 Male Mice

INTRODUCTION

Electronic cigarettes (E-cigs) are in a controversial state. Although E-cig aerosol generally contains fewer harmful substances than smoke from burned traditional cigarettes, aerosol along with other compounds of the E-cigs may also affect lung functions and promote the development of lung-related diseases. We investigated the effects of E-cig on the pulmonary functions of male C57BL/6 mice and reveal the potential underlying mechanisms.

METHODS

A total of 60 male C57BL/6 mice were randomly divided into four groups. They were exposed to fresh-air, traditional cigarette smoke, E-cig vapor with 12 mg/mL of nicotine, and E-cig with no nicotine for 8 weeks. Lung functions were evaluated by using quantitative analysis of the whole body plethysmograph, FlexiVent system, lung tissue histological and morphometric analysis, and RT-PCR analysis of mRNA expression of inflammation-related genes. In addition, the effects of nicotine and acrolein on the survival rate and DNA damage were investigated using cultured human alveolar basal epithelial cells.

RESULTS

Exposure to E-cig vapor led to significant changes in lung functions and structures including the rupture of the alveolar cavity and enlarged alveolar space. The pathological changes were also accompanied by increased expression of interleukin-6 and tumor necrosis factor-α.

CONCLUSIONS

The findings of the present study indicate that the safety of E-cig should be further evaluated.

IMPLICATIONS

Some people currently believe that using nicotine-free E-cigs is a safe way to smoke. However, our research shows that E-cigs can cause lung damage regardless of whether they contain nicotine.

Smoking, Symptoms Improvement, and Total Antioxidant Capacity in Patients with Drug-naive First-episode Schizophrenia: A Prospective Cohort Study

BACKGROUND

It has been hypothesized that smoking is associated with the severity of negative symptoms. Until now, no studies have investigated whether the impact of smoking on negative symptoms is dependent on antioxidants. This study was designed to evaluate the effect of smoking on therapeutic response and total antioxidants capacity (TAOC) in antipsychotic-naïve first-episode (ANFE) patients.

METHODS

The severity of the patient's symptoms was assessed using the Positive and Negative Syndrome Scale (PANSS). A total of 237 ANFE patients were recruited and treated with risperidone (oral tablets, 4-6 mg/day twice a day) for 12 weeks. PANSS was assessed at baseline and a 12-week follow-up. Plasma TAOC levels were also assayed at baseline and week 12.

RESULTS

Relative to nonsmokers with ANFE SZ, smokers had higher PANSS negative subscores. There was no significant difference in TAOC changes after 12 weeks of treatment with risperidone between smokers and non-smokers. However, we found greater improvement in negative symptoms in smokers compared to non-smokers. Further analysis in smokers with SZ demonstrated that improvements in negative symptoms were not associated with changes in TAOC.

CONCLUSION

Our study suggested that smoking affected the severity of baseline negative symptoms and further contributed to their reduction after risperidone treatment. However, improvement in negative symptoms was not dependent on the changes in TAOC.

Duloxetine HCl Alleviates Asthma Symptoms by Regulating PI3K/AKT/mTOR and Nrf2/HO-1 Signaling Pathways

Asthma is an inflammatory disease characterized by airway hyperresponsiveness, airway remodeling, and airway inflammation. In recent years, the prevalence of asthma has been increasing steadily and the pathogenesis of asthma varies from person to person. Due to poor compliance or resistance, existing drugs cannot achieve the desired therapeutic effect. Therefore, developing or screening asthma therapeutic drugs with high curative effects, low toxicity, and strong specificity is very urgent. Duloxetine HCl (DUX) is a selective serotonin and norepinephrine reuptake inhibitor, and it was mainly used to treat depression, osteoarthritis, and neuropathic pain. It was also reported that DUX has potential anti-infection, anti-inflammation, analgesic, antioxidative, and other pharmacological effects. However, whether DUX has some effects on asthma remains unknown. In order to investigate it, a series of ex vivo and in vivo experiments, including biological tension tests, patch clamp, histopathological analysis, lung function detection, oxidative stress enzyme activity detection, and molecular biology experiments, were designed in this study. We found that DUX can not only relax high potassium or ACh precontracted tracheal smooth muscle by regulating L-type voltage-dependent Ca2+ channel (L-VDCC) and nonselective cation channel (NSCC) ion channels but also alleviate asthma symptoms through anti-inflammatory and antioxidative response regulated by PI3K/AKT/mTOR and Nrf2/HO-1 signaling pathways. Our data suggests that DUX is expected to become a potential new drug for relieving or treating asthma.

The therapeutic role of inspiratory muscle training in the management of asthma: a narrative review

Asthma is a disorder of the airways characterized by chronic airway inflammation, hyperresponsiveness, and variable recurring airway obstruction. Treatment options for asthma include pharmacological strategies, whereas nonpharmacological strategies are limited. Established pharmacological approaches to treating asthma may cause unwanted side effects and do not always afford adequate protection against asthma, possibly because of an individual's variable response to medications. A potential nonpharmacological intervention that is most available and cost effective is inspiratory muscle training (IMT), which is a technique targeted at increasing the strength and endurance of the diaphragm and accessory muscles of inspiration. Studies examining the impact of IMT on asthma have reported increases in inspiratory muscle strength and a reduction in the perception of dyspnea and medication use. However, because of the limited number of studies and discordant methods between studies more evidence is required to elucidate in individuals with asthma the efficacy of IMT on inspiratory muscle endurance, exercise capacity, asthma control, symptoms, and quality of life as well as in adolescents with differing severities of asthma. Large randomized controlled trials would be a significant step forward in clarifying the effectiveness of IMT in individuals with asthma. Although IMT may have favorable effects on inspiratory muscle strength, dyspnea, and medication use, the current evidence that IMT is an effective treatment for asthma is inconclusive.

The therapeutic effects of mesenchymal stem cell (MSCs) exosomes in covid-19 disease; Focusing on dexamethasone therapy

The study of diseases, specifically their aetiologies, their step-by-step progressions (pathogenesis), and their impact on normal structure and function, is the focus of pathology, a branch of science and medicine. In therapeutic fields, it is critical to decrease significantly elevated levels of proinflammatory cytokines. The immunomodulatory drugs such as dexamethasone have been used in several of inflammatory diseases such as Covid-19. The use of dexamethasone alone or in combination with other drugs or method such as mesenchymal stem cell (MSC) is one of the most up-to-date discussions about Covid-19. In this review, we first examined the effects of dexamethasone as monotherapy on inflammatory cytokines and then examined studies that used combination therapy of dexamethasone and other drugs such as Baricitinib, Tofacitinib and tocilizumab. Also, therapeutic aspects of MSCs are examined in this review.

Implications of xenobiotic-response element(s) and aryl hydrocarbon receptor in health and diseases

The effect of air pollution on public health is severely detrimental. In humans; the physiological response against pollutants is mainly elicited via the activation of aryl hydrocarbon receptor (AhR). It acts as a prime sensor of xenobiotic chemicals, also functioning as a transcription factor regulating a variety of gene expressions. Along with AhR, another pivotal element of the pollution stress pathway is Xenobiotic Response Elements (XREs). XRE, as studied are some conserved sequences in the DNA, responsible for the physiological response against pollutants. XRE is present at the upstream of the inducible target genes of AhR and it regulates the function of the AhR. XRE(s) are highly conserved in species as it has only eight specific sequences found so far in humans, mice, and rats. Inhalation of toxicants like dioxins, gaseous industrial effluents, and smoke from burning fuel and tobacco leads to predominant damage to the lungs. However, scientists are exploring the involvement of AhR in chronic diseases for example chronic obstructive pulmonary disease (COPD) and also other lethal diseases like lung cancer. In this review, we summarise what is known at this time about the roles played by the XRE and AhR in our molecular systems that have a defined control in the normal maintenance of homeostasis as well as dysfunctions.

Autophagy/Mitophagy in Airway Diseases: Impact of Oxidative Stress on Epithelial Cells

Autophagy is the key process by which the cell degrades parts of itself within the lysosomes. It maintains cell survival and homeostasis by removing molecules (particularly proteins), subcellular organelles, damaged cytoplasmic macromolecules, and by recycling the degradation products. The selective removal or degradation of mitochondria is a particular type of autophagy called mitophagy. Various forms of cellular stress (oxidative stress (OS), hypoxia, pathogen infections) affect autophagy by inducing free radicals and reactive oxygen species (ROS) formation to promote the antioxidant response. Dysfunctional mechanisms of autophagy have been found in different respiratory diseases such as chronic obstructive lung disease (COPD) and asthma, involving epithelial cells. Several existing clinically approved drugs may modulate autophagy to varying extents. However, these drugs are nonspecific and not currently utilized to manipulate autophagy in airway diseases. In this review, we provide an overview of different autophagic pathways with particular attention on the dysfunctional mechanisms of autophagy in the epithelial cells during asthma and COPD. Our aim is to further deepen and disclose the research in this direction to stimulate the develop of new and selective drugs to regulate autophagy for asthma and COPD treatment.

β-Endorphin (an endogenous opioid) inhibits inflammation, oxidative stress and apoptosis via Nrf-2 in asthmatic murine model

Asthma, a chronic respiratory disease is characterized by airway inflammation, remodelling, airflow limitation and hyperresponsiveness. At present, it is considered as an umbrella diagnosis consisting several variable clinical presentations (phenotypes) and distinct pathophysiological mechanisms (endotypes). Recent evidence suggests that oxidative stress participates in airway inflammation and remodelling in chronic asthma. Opioids resembled by group of regulatory peptides have proven to act as an immunomodulator. β-Endorphin a natural and potent endogenous morphine produced in the anterior pituitary gland play role in pain modulation. Therapeutic strategy of many opioids including β-Endorphin as an anti‑inflammatory and antioxidative agent has not been yet explored despite its promising analgesic effects. This is the first study to reveal the role of β-Endorphin in regulating airway inflammation, cellular apoptosis, and oxidative stress via Nrf-2 in an experimental asthmatic model. Asthma was generated in balb/c mice by sensitizing with 1% Toulene Diisocyanate on day 0, 7, 14 and 21 and challenging with 2.5% Toulene Diisocyanate from day 22 to 51 (on every alternate day) through intranasal route. β-Endorphin (5 µg/kg) was administered through the nasal route 1 h prior to sensitization and challenge. The effect of β-Endorphin on pulmonary inflammation and redox status along with parameters of oxidative stress were evaluated. We found that pre-treatment of β-Endorphin significantly reduced inflammatory infiltration in lung tissue and cell counts in bronchoalveolar lavage fluid. Also, pre-treatment of β-Endorphin reduced reactive oxygen species, Myeloperoxidase, Nitric Oxide, Protein and protein carbonylation, Glutathione Reductase, Malondialdehyde, IFN-γ, and TNF-α. Reversely, β-Endorphin significantly increased Superoxide dismutase, Catalase, glutathione, Glutathione-S-Transferase, and activation of NF-E2-related factor 2 (Nrf-2) via Kelch-like ECH-associated protein 1 (Keap1), independent pathway in the lung restoring architectural alveolar and bronchial changes. The present findings reveal the therapeutic potency of β-END in regulating asthma by Keap-1 independent regulation of Nrf-2 activity. The present findings reveal the therapeutic potency of β-Endorphin in regulating asthma.

The role of gut microbiome in the complex relationship between respiratory tract infection and asthma

Asthma is one of the common chronic respiratory diseases in children, which poses a serious threat to children's quality of life. Respiratory infection is a risk factor for asthma. Compared with healthy children, children with early respiratory infections have a higher risk of asthma and an increased chance of developing severe asthma. Many clinical studies have confirmed the correlation between respiratory infections and the pathogenesis of asthma, but the underlying mechanism is still unclear. The gut microbiome is an important part of maintaining the body's immune homeostasis. The imbalance of the gut microbiome can affect the lung immune function, and then affect lung health and cause respiratory diseases. A large number of evidence supports that there is a bidirectional regulation between intestinal flora and respiratory tract infection, and both are significantly related to the development of asthma. The changes of intestinal microbial components and their metabolites in respiratory tract infection may affect the occurrence and development of asthma through the immune pathway. By summarizing the latest advancements in research, this review aims to elucidate the intricate connection between respiratory tract infections and the progression of asthma by highlighting its bridging role of the gut microbiome. Furthermore, it offers novel perspectives and ideas for future investigations into the mechanisms that underlie the relationship between respiratory tract infections and asthma.

Fine particulate matter exposure disturbs autophagy, redox balance and mitochondrial homeostasis via JNK activation to inhibit proliferation and promote EMT in human alveolar epithelial A549 cells

Epidemiologic studies have demonstrated a direct correlation between fine particulate matter (FPM) exposure and the high risk of respiratory diseases. FPM can penetrate deep into the lung and deposit in the alveoli with breath, where it directly interacts with alveolar epithelial cell (APC). However, we know little about the effects nor mechanisms of FPM on APC. Here, using human APC A549 cells, we found that FPM resulted in blockade of autophagic flux, redox imbalance and oxidative stress, mitochondrial fragmentation, increased mitophagy and impaired mitochondrial respiration. Further we showed that activation of JNK signaling (c-Jun N-terminal kinase) and excessive ROS (reactive oxygen species) release contribute to these adverse effects, with the former being upstream of the latter. More importantly, we found that scavenging ROS or inhibiting JNK activation could restore those effects as well as ameliorate FPM-induced inhibition of cell proliferation, and epithelial-mesenchymal transformation (EMT) in A549 cells. Taken together, our findings indicate that FPM leads to toxicity in alveolar type II cells via JNK activation, and JNK-targeting or antioxidant strategies might be beneficial for prevention or treatment of FPM-related pulmonary diseases.

Effect of allyl isothiocyanate on oxidative stress in COPD via the AhR / CYP1A1 and Nrf2 / NQO1 pathways and the underlying mechanism

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is currently the third leading cause of death globally. Oxidative stress affects various molecular mechanisms and is the main driving factor of COPD. Ally isothiocyanate (AITC) is an effective component of Semen Sinapis Albae, which has favorable effects for the treatment of COPD, but its mechanism has not been fully elucidated.

PURPOSE

This study aimed to elucidate the antioxidant effect of AITC on COPD and its molecular mechanism, and preliminarily determine the role of AhR in the progression of COPD.

STUDY DESIGN

The COPD rat model was established by smoking combined with intratracheal instillation of lipopolysaccharide. Different doses of AITC, positive control drug acetylcysteine, AhR inhibitor alpha-naphthoflavone, and agonist beta-naphthoflavone were administered by gavage. Human bronchial epithelial cells induced by cigarette smoke extract (CSE) were used in an in vitro model to explore the molecular mechanisms of AITC.

METHODS

The effects of AITC on lung function and oxidative stress in rats were evaluated in vivo using the respiratory function test, white blood cell count, enzyme-linked immunosorbent assay, and histological staining. The changes in protein expression in the lung tissue were detected by immunohistochemistry and Western blotting. RT-PCR, western blotting, and immunofluorescence were used to explore the molecular mechanisms of AITC. Enzyme-linked immunosorbent assay, reactive oxygen species probing, and flow cytometry were used to determine the antioxidant effect of AITC.

RESULTS

AITC can improve the lung function of rats with COPD, restore lung tissue structure, improve oxidative stress, reduce inflammation, and inhibit lung cell apoptosis. AITC reversed the upregulation of AhR and CYP1A1 and the down-regulation of Nrf2 and NQO1 in the lung tissues of rats with COPD. CSE stimulation can increase the expressions of AhR and CYP1A1 and decrease the expressions of Nrf2 and NQO1 in 16HBE cells, leading to severe oxidative stress and inflammatory response and, ultimately, apoptosis. AITC inhibited AhR and CYP1A1 expressions, induced Nrf2 and NQO1 expressions, promoted Nrf2 nuclear translocation, and improved CSE-induced toxicological effects.

CONCLUSION

AITC may improve lung oxidative stress by inhibiting the AhR / CYP1A1 and activating the Nrf2 / NQO1 pathways, thereby delaying the pathological progression of COPD.

Modulation of oxidative phosphorylation and mitochondrial biogenesis by cigarette smoke influence the response to immune therapy in NSCLC patients

The treatment regimen of non-small cell lung cancer (NSCLC) has drastically changed owing to the superior anti-cancer effects generated by the immune-checkpoint blockade (ICB). However, only a subset of patients experience benefit after receiving ICBs. Therefore, it is of paramount importance to increase the response rate by elucidating the underlying molecular mechanisms and identifying novel therapeutic targets to enhance the efficacy of IBCs in non-responders. We analyzed the progression-free survival (PFS) and overall survival (OS) of 295 NSCLC patients who received anti-PD-1 therapy by segregating them with multiple clinical factors including sex, age, race, smoking history, BMI, tumor grade and subtype. We also identified key signaling pathways and mutations that are enriched in patients with distinct responses to ICB by gene set enrichment analysis (GSEA) and mutational analyses. We found that former and current smokers have a higher response rate to anti-PD-1 treatment than non-smokers. GSEA results revealed that oxidative phosphorylation (OXPHOS) and mitochondrial related pathways are significantly enriched in both responders and smokers, suggesting a potential role of cellular metabolism in regulating immune response to ICB. We also demonstrated that all-trans retinoic acid (ATRA) which enhances mitochondrial function significantly enhanced the efficacy of anti-PD-1 treatment in vivo. Our clinical and bioinformatics based analyses revealed a connection between smoking induced metabolic switch and the response to immunotherapy, which can be the basis for developing novel combination therapies that are beneficial to never smoked NSCLC patients.

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.

Cigarette smoke induces the ROS accumulation and iNOS activation through deactivation of Nrf-2/SIRT3 axis to mediate the human bronchial epithelium ferroptosis

Cigarette smoke (CS)-induced oxidative stress drives the pathogenesis of respiratory diseases, in which the activation and accumulation of reactive oxygen species (ROS) play an important role. Ferroptosis, a regulated cell death induced by Fe²⁺-dependent, lipid peroxidation, and ROS, is closely related to CS-induced airway injury disease, but its mechanism remains unclear. We found that bronchial epithelial ferroptosis and expression of iNOS in smoking patients were significantly higher than that in non-smokers. The iNOS, induced by CS exposure, was involved in bronchial epithelial cell ferroptosis, whereas genetic depletion or pharmacologic inactivation of iNOS attenuated the CS-induced ferroptosis and mitochondrial dysfunction. Our mechanistic studies found that SIRT3 directly bound to and negatively regulated iNOS to mediate ferroptosis. Moreover, we found that the Nrf-2/SIRT3 signal was deactivated by cigarette smoke extract (CSE)-induced ROS. Collectively, these results linked CS to human bronchial epithelial cell ferroptosis through ROS deactivation of the Nrf-2/SIRT3 signal to promote iNOS expression. Our study provides new insights into the pathogenesis of CS-induced tracheal injury diseases such as chronic bronchitis, emphysema, and chronic obstructive pulmonary disease.

Study on the Mechanism of Qing-Fei-Shen-Shi Decoction on Asthma Based on Integrated 16S rRNA Sequencing and Untargeted Metabolomics

Qing-Fei-Shen-Shi decoction (QFSS) consists of Prunus armeniaca L., Gypsum Fibrosum, Smilax glabra Roxb., Coix lacryma-jobi L., Benincasa hispida (Thunb.) Cogn., Plantago asiatica L., Pyrrosia lingua (Thunb.) Farw., Houttuynia cordata Thunb., Fritillaria thunbergii Miq., Cicadae Periostracum, and Glycyrrhizae Radix Et Rhizoma Praeparata Cum Melle. QFSS shows significant clinical efficacy in the treatment of asthma. However, the specific mechanism of QFSS on asthma remains unclear. Recently, multiomics techniques are widely used in elucidating the mechanisms of Chinese herbal formulas. The use of multiomics techniques can better illuminate the multicomponents and multitargets of Chinese herbal formulas. In this study, ovalbumin (OVA) was first employed to induce an asthmatic mouse model, followed by a gavage of QFSS. First, we evaluated the therapeutic effects of QFSS on the asthmatic model mice. Second, we investigated the mechanism of QFSS in treating asthma by using an integrated 16S rRNA sequencing technology and untargeted metabolomics. Our results showed that QFSS treatment ameliorated asthma in mice. In addition, QFSS treatment affected the relative abundances of gut microbiota including Lactobacillus, Dubosiella, Lachnospiraceae_NK4A136_group, and Helicobacter. Untargeted metabolomics results showed that QFSS treatment regulated the metabolites such as 2-(acetylamino)-3-[4-(acetylamino) phenyl] acrylic acid, D-raffinose, LysoPC (15 : 1), methyl 10-undecenoate, PE (18 : 1/20 : 4), and D-glucose6-phosphate. These metabolites are associated with arginine and proline metabolism, arginine biosynthesis, pyrimidine metabolism, and glycerophospholipid metabolism. Correlation analysis indicated that arginine and proline metabolism and pyrimidine metabolism metabolic pathways were identified as the common metabolic pathways of 16s rRNA sequencing and untargeted metabolomics. In conclusion, our results showed that QFSS could ameliorate asthma in mice. The possible mechanism of QFSS on asthma may be associated with regulating the gut microbiota and arginine and proline metabolism and pyrimidine metabolism. Our study may be useful for researchers to study the integrative mechanisms of Chinese herbal formulas based on modulating gut microbiota and metabolism.

Ketamine Attenuates Airway Inflammation via Inducing Inflammatory Cells Apoptosis and Activating Nrf2 Pathway in a Mixed-Granulocytic Murine Asthma Model

Purpose

The use of ketamine, an anesthetic, as a treatment for asthma has been investigated in numerous studies. However, how ketamine affects asthma is unclear. The present study examined the effects of ketamine on a murine model of mixed-granulocytic asthma, and the role of the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway.

Methods

The murine model of mixed-granulocytic asthma was established using ovalbumin (OVA) for sensitization and the combination of OVA and lipopolysaccharides (LPS) for challenge. The main characteristics of asthma, oxidative stress biomarkers, and the expression of the Nrf2 pathway were examined. ML385 was administered to verify the role of the Nrf2 pathway.

Results

Mice in the OVA +LPS group developed asthmatic characteristics, including airway hyperresponsiveness, mixed-granulocytic airway inflammation, mucus overproduction, as well as increased levels of oxidative stress and impaired apoptosis of inflammatory cells. Among the three concentrations, ketamine at 75mg/kg effectively attenuated these asthmatic symptoms, activated the Nrf2 pathway, decreased oxidative stress, and induced apoptosis of eosinophils and neutrophils in bronchoalveolar lavage fluid (BALF) with a reducing level of myeloid cell leukemia 1(Mcl-1). ML385 (an Nrf2 inhibitor) eliminated the protective effects of ketamine on the mixed-granulocytic asthma model.

Conclusion

The study concluded that ketamine reduced oxidative stress and attenuated asthmatic symptoms (neutrophilic airway inflammation) by activating the Nrf2-Keap1 pathway, with 75 mg/kg ketamine showing the best results. Ketamine administration also increased neutrophil and eosinophil apoptosis in BALF, which may contribute to the resolution of inflammation. The use of ketamine as a treatment for asthma may therefore be beneficial.

Overview of the Mechanisms of Oxidative Stress: Impact in Inflammation of the Airway Diseases

Inflammation of the human lung is mediated in response to different stimuli (e.g., physical, radioactive, infective, pro-allergenic or toxic) such as cigarette smoke and environmental pollutants. They often promote an increase in inflammatory activities in the airways that manifest themselves as chronic diseases (e.g., allergic airway diseases, asthma, chronic bronchitis/chronic obstructive pulmonary disease (COPD) or even lung cancer). Increased levels of oxidative stress (OS) reduce the antioxidant defenses, affect the autophagy/mitophagy processes, and the regulatory mechanisms of cell survival, promoting inflammation in the lung. In fact, OS potentiate the inflammatory activities in the lung, favoring the progression of chronic airway diseases. OS increases the production of reactive oxygen species (ROS), including superoxide anions (O₂^-), hydroxyl radicals (OH) and hydrogen peroxide (H₂O₂), by the transformation of oxygen through enzymatic and non-enzymatic reactions. In this manner, OS reduces endogenous antioxidant defenses in both nucleated and non-nucleated cells. The production of ROS in the lung can derive from both exogenous insults (cigarette smoke or environmental pollution) and endogenous sources such as cell injury and/or activated inflammatory and structural cells. In this review, we describe the most relevant knowledge concerning the functional interrelation between the mechanisms of OS and inflammation in airway diseases.

The role of HMGB1/RAGE/TLR4 signaling pathways in cigarette smoke-induced inflammation in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a common chronic respiratory disease with irreversible and continuous progression. It has become the fifth most burdensome disease and the third most deadly disease globally. Therefore, the prevention and treatment of COPD are urgent, and it is also important to clarify the pathogenesis of it. Smoking is the main and most common risk factor for COPD. Cigarette smoke (CS) can cause lung inflammation and other pathological mechanisms in the airways and lung tissue. Airway inflammation is one of the important mechanisms leading to the pathogenesis of COPD. Recent studies have shown that high mobility group box 1 (HMGB1) is involved in the occurrence and development of respiratory diseases, including COPD. HMGB1 is a typical damage-associated molecular pattern (DAMP) protein, which mainly exerts its activity by binding to the receptor for advanced glycation end products (RAGE) and toll-like receptor 4 (TLR4) and further participate in the process of airway inflammation. Studies have shown that the abnormal expression of HMGB1, RAGE, and TLR4 are related to inflammation in COPD. Herein, we discuss the roles of HMGB1, RAGE, and TLR4 in CS/cigarette smoke extract-induced inflammation in COPD, providing a new target for the diagnosis, treatment and prevention of COPD.

Smoke, GPx activity and symptoms improvement in patients with drug-naive first-episode schizophrenia: A large-scale 12-week follow-up study

The relationship between tobacco smoke and schizophrenia (SZ) is well established. Smoking is hypothesized to alleviate symptoms and reduce the adverse effects of antipsychotic medications in patients with SZ. However, the underlying biological mechanisms by which smoke improves symptoms in SZ remain unclear. The aim of this study was to investigate the effect of smoking on clinical symptoms and antioxidant enzyme activity after risperidone treatment in a 12-week prospective cohort study of drug-naïve first-episode (DNFE) SZ patients. Two hundred and fifteen DNFE patients were recruited and received 12 weeks of risperidone monotherapy. The Positive and Negative Syndrome Scale (PANSS) was used to assess the severity of patient's symptoms at baseline and post-treatment. Plasma GPx activity was also measured at baseline and at the end of 12 weeks. Smokers showed greater improvement in negative symptoms relative to nonsmokers with DNFE SZ. In addition, repeated ANCOVA analysis showed no significant interaction of time and group on GPx activity. Improvement in negative symptoms was not associated with changes in GPx activity. However, in nonsmokers, increased GPx activity was correlated with improvement in positive symptoms.

Pharmacological OGG1 inhibition decreases murine allergic airway inflammation

Background and aim: Allergic asthma is a complex inflammatory disease involving type 2 innate lymphoid cells, type 2 T helper cells, macrophages, and eosinophils. The disease is characterized by wheezing, dyspnea, coughing, chest tightness and variable airflow limitation for which there is no cure and is symptomatically treated with inhaled corticosteroids and β2-agonists. Molecular mechanisms underlying its complex pathogenesis are not fully understood. However, 8-oxoguanine DNA glycosylase-1 (OGG1), a DNA repair protein may play a central role, as OGG1 deficiency decreases both innate and allergic inflammation.

Methods: Using a murine ovalbumin (OVA) model of allergic airway inflammation we assessed the utility of an inhibitor of OGG1 (TH5487) in this disease context. Cytokines and chemokines, promoting immune cell recruitment were measured using a 23-multiplex assay and Western blotting. Additionally, immune cell recruitment to bronchi was measured using flow cytometry. Histological analyses and immunofluorescent staining were used to confirm immune cell influx and goblet cell hyperplasia of the airways. A PCR array was used to assess asthma-related genes in murine lung tissue following TH5487 treatment. Finally, airway hyperresponsiveness was determined using in vivo lung function measurement.

Results: In this study, administration of TH5487 to mice with OVA-induced allergic airway inflammation significantly decreased goblet cell hyperplasia and mucus production. TH5487 treatment also decreased levels of activated NF-κB and expression of proinflammatory cytokines and chemokines resulting in significantly lower recruitment of eosinophils and other immune cells to the lungs. Gene expression profiling of asthma and allergy-related proteins after TH5487 treatment revealed differences in several important regulators, including down regulation of Tnfrsf4, Arg1, Ccl12 and Ccl11, and upregulation of the negative regulator of type 2 inflammation, Bcl6. Furthermore, the gene Clca1 was upregulated following TH5487 treatment, which should be explored further due to its ambiguous role in allergic asthma. In addition, the OVA-induced airway hyperresponsiveness was significantly reduced by TH5487 treatment.

Conclusion: Taken together, the data presented in this study suggest OGG1 as a clinically relevant pharmacological target for the treatment of allergic inflammation.

The Impact of Tobacco Cigarettes, Vaping Products and Tobacco Heating Products on Oxidative Stress

Cells constantly produce oxidizing species because of their metabolic activity, which is counteracted by the continuous production of antioxidant species to maintain the homeostasis of the redox balance. A deviation from the metabolic steady state leads to a condition of oxidative stress. The source of oxidative species can be endogenous or exogenous. A major exogenous source of these species is tobacco smoking. Oxidative damage can be induced in cells by chemical species contained in smoke through the generation of pro-inflammatory compounds and the modulation of intracellular pro-inflammatory pathways, resulting in a pathological condition. Cessation of smoking reduces the morbidity and mortality associated with cigarette use. Next-generation products (NGPs), as alternatives to combustible cigarettes, such as electronic cigarettes (e-cig) and tobacco heating products (THPs), have been proposed as a harm reduction strategy to reduce the deleterious impacts of cigarette smoking. In this review, we examine the impact of tobacco smoke and MRPs on oxidative stress in different pathologies, including respiratory and cardiovascular diseases and tumors. The impact of tobacco cigarette smoke on oxidative stress signaling in human health is well established, whereas the safety profile of MRPs seems to be higher than tobacco cigarettes, but further, well-conceived, studies are needed to better understand the oxidative effects of these products with long-term exposure.

Computational Insights into the Regeneration of Ovothiol and Ergothioneine and Their Selenium Analogues by Glutathione

Ovothiol and ergothioneine are powerful antioxidants that readily react with oxidants by forming their respective disulfides. In fact, ovothiol is widely considered one of the most powerful natural antioxidants. However, for these antioxidants to be again involved in reacting with oxidants, they must be regenerated via the reduction of the disulfide bonds. In the present work, the regeneration of the antioxidants ovothiol and ergothioneine and their selenium analogues, by the closed-shell nucleophilic attack of glutathione, was investigated using density functional theory. From the calculated thermodynamic data, the attack of glutathione on OSSO and EYYE (where Y = S and/or Se) will readily occur in solution. Moreover, in comparison to the reference reaction GSH + GSSG → GSSG + GSH, all reactions are expected to be faster. Overall, the results presented herein show that the key antioxidant GSH should readily recycle ovothiol, ovoselenol, ergothioneine, and ergoseloneine from OYYO and EYYE (where Y = S and/or Se).

Plasma Lipid Profiling Identifies Phosphatidylcholine 34:3 and Triglyceride 52:3 as Potential Markers Associated with Disease Severity and Oxidative Status in Chronic Obstructive Pulmonary Disease

PURPOSE

To identify plasma alterations in lipid species in patients with chronic obstructive pulmonary disease (COPD), as well as, relationships with smoking status, oxidative and inflammatory markers.

METHODS

Plasma was obtained from 100 patients with COPD and 120 healthy controls. Pulmonary function was assessed by plethysmography. Serum levels of IL-6 and TNF-α were determined by ELISA. Oxidative stress parameters were measured using standard methods. Lipids were extracted then analyzed by Matrix-Assisted Laser Desorption and Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF-TOF-MS).

RESULTS

More than 40 lipid compounds were identified within plasma samples. Among these 19 lipid species including plasmalogens (PC O-), phosphatidylcholines (PC), and triglycerides (TG) were significantly altered in COPD. A decreased expression of PC O- (36:1, 36:2, 36:3, 36:4, 38:4, 38:5) species was found in patients with different severities compared to healthy controls. There was also a decrease in PC (34:3, 36:0, 36:4, 36:5, 40:6, 40:7) species in COPD patients. PC (34:3) levels were positively correlated with disease progression and pulmonary function decline (forced expiratory volume in 1 s (FEV₁)) (r = 0.84, p < 0.001) and inversely correlated with thiobarbituric acid-reactive substances (TBARS) (r = - 0.77, p < 0.001). TG (50:0, 50:1, 52:1, 52:2, 52:3, 52:4, 54:4) species were altered in COPD patients and in those with advanced disease stages. Significant correlations between FEV₁, TBARS, peroxynitrite, and TG (52:3) were found among COPD patients (r = - 0.69; r = 0.86; r = 0.77, p < 0.001, respectively).

CONCLUSION

PC (34:3) and TG (52:3) could be potential lipid signatures of COPD that correlate with altered pulmonary function and oxidative status.

Benzo[a]pyrene-Environmental Occurrence, Human Exposure, and Mechanisms of Toxicity

Benzo[a]pyrene (B[a]P) is the main representative of polycyclic aromatic hydrocarbons (PAHs), and has been repeatedly found in the air, surface water, soil, and sediments. It is present in cigarette smoke as well as in food products, especially when smoked and grilled. Human exposure to B[a]P is therefore common. Research shows growing evidence concerning toxic effects induced by this substance. This xenobiotic is metabolized by cytochrome P450 (CYP P450) to carcinogenic metabolite: 7β,8α-dihydroxy-9α,10α-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (BPDE), which creates DNA adducts, causing mutations and malignant transformations. Moreover, B[a]P is epigenotoxic, neurotoxic, and teratogenic, and exhibits pro-oxidative potential and causes impairment of animals' fertility. CYP P450 is strongly involved in B[a]P metabolism, and it is simultaneously expressed as a result of the association of B[a]P with aromatic hydrocarbon receptor (AhR), playing an essential role in the cancerogenic potential of various xenobiotics. In turn, polymorphism of CYP P450 genes determines the sensitivity of the organism to B[a]P. It was also observed that B[a]P facilitates the multiplication of viruses, which may be an additional problem with the widespread COVID-19 pandemic. Based on publications mainly from 2017 to 2022, this paper presents the occurrence of B[a]P in various environmental compartments and human surroundings, shows the exposure of humans to this substance, and describes the mechanisms of its toxicity.

Carboxymethyl Chitosan Modified Oxymatrine Liposomes for the Alleviation of Emphysema in Mice via Pulmonary Administration

Pulmonary emphysema is a fatal lung disease caused by the progressive thinning, enlargement and destruction of alveoli that is closely related to inflammation and oxidative stress. Oxymatrine (OMT), as a bioactive constituent of traditional Chinese herbal Sophora flavescens, has great potential to alleviate pulmonary emphysema via its anti-inflammatory and antioxidative activities. Pulmonary administration is the most preferable way for the treatment of lung diseases. To improve the in vivo stability and pulmonary retention of OMT, OMT-loaded liposome with carboxymethyl chitosan (CMCS) modification was developed. The CMCS was modified on the surface of OMT liposomes via electrostatic attraction and covalent conjugation to obtain Lipo/OMT@CMCS and CMCS-Lipo/OMT, respectively. A porcine pancreatic elastase (PPE)-induced emphysema mice model was established to evaluate the alleviation effects of OMT on alveolar expansion and destruction. CMCS-modified liposomal OMT exhibited superior ameliorative effects on emphysema regardless of the preparation methods, and higher sedimentation and longer retention in the lung were observed in the CMCS-Lipo group. The mechanisms of OMT on emphysema were related to the downregulation of inflammatory cytokines and the rebalancing of antioxidant/oxidation via the Nrf2/HO-1 and NF-κB/IκB-α signaling pathways, leading to reduced cell apoptosis. Moreover, the OMT liposomal preparations further enhanced its anti-inflammatory and antioxidative effects. In conclusion, pulmonary administration of OMT is a potential strategy for the treatment of emphysema and the therapeutic effects can be further improved by CMCS-modified liposomes.

Metabolomics in asthma: A platform for discovery

Asthma, characterized by airway hyperresponsiveness, inflammation and remodeling, is a chronic airway disease with complex etiology. Severe asthma is characterized by frequent exacerbations and poor therapeutic response to conventional asthma therapy. A clear understanding of cellular and molecular mechanisms of asthma is critical for the discovery of novel targets for optimal therapeutic control of asthma. Metabolomics is emerging as a powerful tool to elucidate novel disease mechanisms in a variety of diseases. In this review, we summarize the current status of knowledge in asthma metabolomics at systemic and cellular levels. The findings demonstrate that various metabolic pathways, related to energy metabolism, macromolecular biosynthesis and redox signaling, are differentially modulated in asthma. Airway smooth muscle cell plays pivotal roles in asthma by contributing to airway hyperreactivity, inflammatory mediator release and remodeling. We posit that metabolomic profiling of airway structural cells, including airway smooth muscle cells, will shed light on molecular mechanisms of asthma and airway hyperresponsiveness and help identify novel therapeutic targets.

Associations Between Chronic Rhinosinusitis and Cancers: A Nationwide Population-Based Cohort Study

OBJECTIVE

Chronic rhinosinusitis (CRS) is one of the most common chronic inflammatory diseases. The effect of chronic inflammation caused by CRS on the occurrence of various cancers has not been thoroughly evaluated. This study aimed to investigate the increased incidences of 10 types of cancers among CRS patients with/without nasal polyps (NP) using a national population-based database from the Korean Health Insurance Review and Assessment Service.

STUDY DESIGN

A case-control cohort study.

METHODS

We compared the prevalence of various comorbidities between CRS and control participants from a national cohort dataset of the Korean Health Insurance Review and Assessment Service.

METHODS

CRS participants (n = 6,919) and non-CRS (n = 27,676) participants were selected from among the 514,866 participants from 2002 to 2015. A stratified Cox proportional hazards model was utilized to assess the hazard ratio (HR) of CRS for 10 types of cancers.

RESULTS

A stratified Cox proportional hazard model demonstrated that the adjusted HR for hematologic malignancy was significantly higher in the CRS patients than in the controls regardless of the presence of NP (2.90 for total CRS; 2.15 for CRS with NP; 4.48 for CRS without NP). The HR for thyroid cancer was significantly higher in the CRS patients without NP but not in those with NP (1.50 for total CRS; 1.78 for CRS without NP).

CONCLUSION

This study showed that CRS participants had a significantly higher prevalence of hematologic malignancy and thyroid cancer.

LEVEL OF EVIDENCE

4 Laryngoscope, 2022.

Oxidative stress in patients with asthma and its relation to uncontrolled asthma

This study aims to evaluate markers of oxidative stress in Tunisian asthmatic patients and investigate whether their markers are correlated with uncontrolled asthma.

This prospective cohort study was conducted on 48 healthy subjects and 60 patients with asthma (34 patients with controlled asthma and 26 patients with uncontrolled asthma). The levels of malondialdehyde (MDA), advanced oxidation protein products (AOPP), and glutathione (GSH), as well as the activities of glutathione peroxidase (GPx) and superoxide dismutase (SOD), were estimated in plasma by spectrophotometry.

Asthmatic patients have significantly higher plasmatic levels of MDA and AOPP than healthy controls (p < 0.001). Lower GSH level and GPx activity were found in patients with asthma compared to controls (p < 0.001). In contrast, higher SOD activity was noted in asthmatic patients (p < 0.001).

The comparison among the patients with controlled asthma and uncontrolled asthma revealed increased MDA and AOPP levels and SOD activity (p < 0.001) as well as a decreased GSH level and GPx activity (p = 0.004, p = 0.019) in patients with uncontrolled asthma. Spirometry level was significantly correlated with SOD activity (r = 0.447; p = 0.010), whereas no significant correlations were found with the other parameters (MDA, AOPP, GSH, and GPx).

Asthmatic patients, especially those with uncontrolled asthma, suffer a high degree of reactive oxygen species (ROS) formation causing considerable oxidative stress. Increased MDA level and SOD activity and reduced GPx activity were predictors of poorly controlled asthma.

Transcriptomic and metabolomic associations with exposures to air pollutants among young adults with childhood asthma history

Ambient air pollutants are well-known risk factors for childhood asthma and asthma exacerbation. It is unknown whether different air pollutants individually or jointly affect pathophysiological mechanisms of asthma. In this study, we aim to integrate transcriptome and untargeted metabolome to identify dysregulated genetic and metabolic pathways that are associated with exposures to a mixture of ambient and traffic-related air pollutants among adults with asthma history. In this cross-sectional study, 102 young adults with childhood asthma history were enrolled from southern California in 2012. Whole blood transcriptome was measured with 20,869 expression signatures, and serum untargeted metabolomics including 937 metabolites were analyzed by Metabolon, Inc. Participants' exposures to regional air pollutants (NO₂, O₃, PM₁₀, PM_2.5) and near-roadway air pollutants averaged at one month and one year before study visit were estimated based on residential addresses. xMWAS network analysis and joint-pathway analysis were performed to identify subnetworks and genetic and metabolic pathways that were associated with exposure to air pollutants adjusted for socio-characteristic covariates. Network analysis found that exposures to air pollutants mixture were connected to 357 gene markers and 92 metabolites. One-year and one-month averaged PM_2.5 and NO₂ were associated with several amino acids related to serine, glycine, and beta-alanine metabolism. Lower serum levels of carnosine and aspartate, which are involved in the beta-alanine metabolic pathway, as well as choline were also associated with worse asthma control (p < 0.05). One-year and one-month averaged PM₁₀ and one-month averaged O₃ were associated with higher gene expression levels of HSPA5, LGMN, CTSL and HLA-DPB1, which are involved in antigen processing and presentation. These results indicate that exposures to various air pollutants are associated with altered genetic and metabolic pathways that affect anti-oxidative capacity and immune response and can potentially contribute to asthma-related pathophysiology.

PM2.5 Exposure and Asthma Development: The Key Role of Oxidative Stress

Oxidative stress is defined as the imbalance between reactive oxygen species (ROS) production and the endogenous antioxidant defense system, leading to cellular damage. Asthma is a common chronic inflammatory airway disease. The presence of asthma tends to increase the production of reactive oxygen species (ROS), and the antioxidant system in the lungs is insufficient to mitigate it. Therefore, asthma can lead to an exacerbation of airway hyperresponsiveness and airway inflammation. PM2.5 exposure increases ROS levels. Meanwhile, the accumulation of ROS will further enhance the oxidative stress response, resulting in DNA, protein, lipid, and other cellular and molecular damage, leading to respiratory diseases. An in-depth study on the relationship between oxidative stress and PM2.5-related asthma is helpful to understand the pathogenesis and progression of the disease and provides a new direction for the treatment of the disease. This paper reviews the research progress of oxidative stress in PM2.5-induced asthma as well as highlights the therapeutic potentials of antioxidant approaches in treatment of asthma.