Role of IL-6 in asthma and other inflammatory pulmonary diseases

Store-operated Ca2+ entry contributes to the ASM phenotype transition in asthma

AIM OF THE STUDY

Phenotype modulation of airway smooth muscle cells (ASMC), characterized by a shift toward a more proliferative and synthetic phenotype from contractile cells, plays a crucial role in airway remodeling in asthma. STIM1 and Orai1, key components of store-operated Ca2+ entry (SOCE), have been demonstrated to enhance ASMC proliferation and migration. This study investigated the impact of STIM1/Orai1-mediated SOCE on ASMC phenotype transition and extracellular matrix (ECM) deposition in asthma.

MATERIALS AND METHODS

The ASMCs were treated with PDGF-BB and SOCE inhibitors. Immunocytochemistry staining, enzyme-linked immunosorbent assay, and western blot assay were employed to detect the ASMC's proliferation as well as the expressions of contractile proteins, inflammatory cytokines and ECM. Moreover, the effect of SOCE repression in ECM deposition were evaluated in an asthmatic mouse model.

RESULTS

ASMCs from airways of mice were treated with PDGF-BB to induce the 'proliferative/synthetic' phenotype. We observed elevated expressions of STIM1 and Orai1 in phenotype-switched ASMCs, along with enhanced SOCE. SKF-96365 and RO2959, which target of STIM1/Orai1, could significantly inhibit SOCE activation in ASMCs. Moreover, these SOCE inhibitors mitigated the elevated proliferation rate, decreased the secretion of inflammatory cytokines and restored the reduced levels of contractile proteins in phenotype-switched ASMCs induced by PDGF-BB. Furthermore, we observed that PDGF-BB-induced 'proliferative/synthetic' ASMCs exhibited increased production of ECM components, including collagen I and fibronectin, as well as metalloproteinases (MMPs) such as MMP2 and MMP9, all of which were effectively inhibited by SKF-96365 and RO2959. In vivo experiments also demonstrated that SOCE inhibitors decreased ECM deposition and MMPs production in the asthmatic mouse model.

CONCLUSIONS

These findings underscored the significant role of STIM1/Orai1-mediated SOCE in ASMC phenotype modulation and its impact on the excessive ECM deposition driven by ASMCs. Thus, our findings suggest that STIM1/Orai1-mediated SOCE may contribute to airway remodeling in asthma.

Targeting alarmins in asthma: From bench to clinic

Over the past 2 decades, mechanistic studies of allergic and type 2 (T2)-mediated airway inflammation have led to multiple approved therapies for the treatment of moderate-to-severe asthma. The approval and availability of these monoclonal antibodies targeting IgE, a T2 cytokine (IL-5) and/or cytokine receptors (IL-5Rα, IL-4Rα) has been central to the progresses made in the management of moderate-to-severe asthma over this period. However, there are persistent gaps in clinician's ability to provide precise care, given that many patients with T2-high asthma do not respond to IgE- or T2 cytokine-targeting therapies and that patients with T2-low asthma have few therapeutic options. The new frontier of precision medicine in asthma, as well as in other allergic diseases, includes the targeting of epithelium-derived cytokines known as alarmins, including thymic stromal lymphopoietin, IL-25, IL-33, and their receptors. The effects of these alarmins, which can act upstream of immune cells, involve both the innate and adaptive systems and hold potential for the treatment of both T2-high and -low disease. Tezepelumab, an anti-thymic stromal lymphopoietin antibody, has already been approved for the treatment of severe asthma. In this review, we discuss our current understanding of alarmin biology with a primary focus on allergic airway diseases. We link the mechanistic corollaries to the clinical implications and advances in drug development targeting alarmins, with a particular focus on currently approved treatments, those under study, and future potential targets in alarmin signaling pathways.

A systematic pharmacological strategy-based to decode the synergistic mechanism of 7,4'-dihydroxyflavone in combination with vitamin D3 against asthma

ETHNOPHARMACOLOGICAL RELEVANCE

7,4'-dihydroxyflavone (74DHF), extracted from Gancao (Rhizoma Glycyrrhizae), has demonstrated to mediate the asthma pathology, while Vitamin D3 (VD3) plays a role in asthma treatment due to its immunomodulatory effects. However, the potential molecular or systems mechanism of 74DHF in combination with VD3 against asthma has not yet been elucidated.

AIM OF THE STUDY

The current study not only deepens our understanding of the complex synergistic mechanism of 74DHF andVD3 against asthma but also proposes a promising strategy to promote the development of combination therapy.

MATERIALS AND METHODS

This study employed a systems pharmacology-based approach integrating target fishing, data integration, bioinformatics analysis, network analysis, Gene Ontology (GO) enrichment analysis, pathway analysis, and in vitro experiment validation to elucidate the pharmacological mechanisms of the combination of 74DHF and VD3 for asthma treatment.

RESULTS

Our investigation revealed 47 overlapping targets, 20 core targets, 10 optimal common GO processes, and 10 key pathways closely associated with asthma in the combination of 74DHF and VD3. The combined treatment of 74DHF and VD3 inhibited the inflammatory response (TNF-α and IL-6) induced by LPS in macrophages and epithelial to mesenchymal transition (EMT) related genes expression (CDH1 and ACTA2) in bronchial epithelial cells under the stimulation of TGF-β1.

CONCLUSION

The present study deciphered the molecular mechanism of combined therapeutic effect of 74DHF and VD3 on asthma on systemic and cellular level.

Zhichuanling injection improves bronchial asthma by attenuation airway inflammation and epithelia-mesenchymal transition

ETHNOPHARMACOLOGICAL RELEVANCE

Zhichuanling (ZCL) Injection, is a compound formulation containing extracts of mahuang (Herba Ephedrae, dried stem or aerial part of Ephedra sinica Stapf), bitter almond (Semen Armeniacae Amarum, seeds of Prunus armeniaca var. sibirica (L.) K. Koch), yangjinhua (flower of Datura metel L.) and Fructus Forsythiae (fruits of Forsythia suspensa (Thunb.) Vahl). Intramuscular injection of ZCL has been used in the clinical practice to control asthma. The aerosol inhalation of ZCL has been shown to be effective on allergic bronchial asthma. However, the underlying mechanisms remain established.

AIM OF THE STUDY

To investigate the underling mechanism by which ZCL inhibits the pathogenesis of bronchial asthma.

METHODS

The guinea pig tracheal rings and human bronchial epithelial (16HBE) cells were used to assess ZCL's impact on acetylcholine (Ach) induced tracheal contraction, tumor necrosis factor α (TNF-α) induced bronchial inflammation, and transforming growth factor-β1 (TGF-β1) induced airway remodeling. Cell viability and gene expression were assessed using MTT assays, qPCR. RNA-seq (gene expression analysis) was employed to explore the novel mechanisms of ZCL in OVA-induced bronchial asthma.

RESULTS

In this study, we found that ZCL reduces Ach-induced contraction of isolated guinea pig trachea, suppress TNF-α-induced interleukin (IL)-1β, IL-6, and IL-8 and TGF-β1-induced E-cadherin, α-SMA, Vimentin, N-cadherin mRNA expression in the 16HBE. Transcriptomic analysis of lung tissue from mice with OVA-induced bronchial asthma suggests that ZCL may alleviate asthma symptoms by modulating BPIFA1, HIF3Α, CTXN3, GRFA3, PPEF1, KSR2, and CDSN.

CONCLUSION

ZCL alleviates asthma by suppressing tracheal contractions, inflammation, and epithelial-to-mesenchymal transition. ZCL effect on asthma is likely through the upregulation of BPIFA1 expression thus providing the molecular insight for the treatment of asthma. The findings suggest that ZCL holds promise as a asthma therapeutic approach, and further research is needed to explore its full clinical potential. Future studies should focus on optimizing dosage, evaluating long-term efficacy, and investigating potential synergistic effects with existing treatments to enhance asthma management and patient outcomes.

The J-shaped relationship between body roundness index and adult asthma: insights from NHANES 2001-2018

Background

Many studies have used Body Mass Index (BMI) to define obesity and examine its potential link to adult asthma. However, BMI overlooks body fat distribution, which may significantly impact health. Unlike BMI, the Body Roundness Index (BRI) can more accurately reflect body fat distribution. Therefore, this study examined BRI's relationship with asthma prevalence in U.S. adults.

Methods

This study was based on data from the National Health and Nutrition Examination Survey (NHANES) between 2001 and 2018 and covered 40,052 adult participants. Participants were categorized into four quartile groups based on their BRI levels: Quartile 1 (1.05, 3.80); Quartile 2 (3.80, 5.06); Quartile 3 (5.06, 6.61); Quartile 4 (6.61, 23.48). The association between BRI and asthma prevalence was assessed via weighted multivariate logistic regression, smoothed curve fitting, threshold effects, subgroup, and sensitivity analysis. BRI's predictive power was compared to BMI and waist circumference using z-scores.

Results

Of the study population, 5,605 participants had asthma (13.99% prevalence). After adjusting for possible confounders, the results showed that higher BRI was linked to greater asthma prevalence (OR = 1.41, 95% CI:1.27, 1.56, p < 0.0001). A J-shaped relationship between BRI and asthma prevalence (p-nonlinearity = 0) was found, with asthma prevalence rising significantly when BRI surpassed 4.34. BRI outperformed BMI and waist circumference in predicting asthma (BRI: OR = 1.180; BMI: OR = 1.169; W.C.: OR = 1.166). Subgroup and sensitivity analyses confirmed our results' robustness.

Conclusion

Adult asthma prevalence increases with increasing BRI levels, showing a J-shaped relationship. Keeping BRI under 4.34 is vital for lowering asthma prevalence, especially for overweight or obese individuals. In addition, BRI outperformed BMI and waist circumference in predicting asthma occurrence.

High Interleukin (IL)-6 is Associated with Lower Lung Function and Increased Likelihood of Metabolic Dysfunction in Asthma

INTRODUCTION

Asthma is a complex condition characterized by airway inflammation. Interleukin-6 (IL-6) plays a significant role in asthma pathogenesis through its effects on T cells and its association with pro-inflammatory responses. Both lung and circulating IL-6 levels are elevated in asthma. IL-6 is positively associated with disease severity, frequent exacerbations, and impaired lung function, all of which can be observed clinically. We developed an IL-6 cut-off model to examine the association between high IL-6, race, high body mass index (BMI), metabolic disease, and asthma severity as assessed by reduced lung function.

METHODS

This study utilized the Coronary Artery Risk Development in Young Adults (CARDIA) database, comprised of 5115 adults, to investigate the relationship between IL-6 levels, asthma, race, and metabolic dysfunction. A "healthy" subset of 427 patients was used to compute the IL-6 cut-off. IL-6 levels within detection limits (0.15-12 pg/mL) were analyzed. The IL-6 cut-off was determined using the 95th percentile of log-transformed IL-6 values for lean (BMI < 25) and healthy individuals. Specific cut-offs were established for racial groups. Statistical analyses involved comparing patient characteristics between high and low IL-6 groups, regression analyses, and assessment of factors influencing lung function changes.

RESULTS

Using an IL-6 cut-off of 4.979 pg/mL, the cohort was divided into high and low IL-6 groups. High IL-6 correlated with Black race, higher BMI, hypertension, and markers of metabolic dysfunction, e.g., elevated HbA1c, C-reactive protein (CRP), and reduced lung function. Multivariable analysis linked high IL-6 with male gender, high BMI, Black race, HbA1c, CRP, and inversely with lung function and total cholesterol. Obesity showed a consistent positive association with elevated IL-6, regardless of the presence or absence of asthma. Patients with asthma and high IL-6 were more likely to be Black and showed increased CRP. Lung function was lowest in non-lean, high IL-6 patients with asthma, with similar trends in non-lean (BMI ≥ 25) patients without asthma.

CONCLUSION

This study underscores the significant association between IL-6, asthma, obesity, and metabolic dysfunction. Elevated IL-6 correlates with asthma severity, particularly in individuals with obesity. Future research should explore anti-IL-6 therapies for specific phenotypes, such as obesity-related asthma. These findings advance our understanding of asthma and the role of IL-6 in its pathogenesis.

Lsm2 is critical to club cell proliferation and its inhibition aggravates COPD progression

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a prevalent respiratory condition, with its severity inversely related to the levels of Club cell 10 kDa secretory protein (CC10). The gene Lsm2, involved in RNA metabolism and cell proliferation, has an unclear role in COPD development.

METHODS

An in vitro COPD model was developed by stimulating 16HBE cells with cigarette smoke extract (CSE). To establish an in vivo COPD model, mice with defective Lsm2 gene expression in lung or club cells were exposed to cigarette smoke for 3 months. Multiplexed immunohistochemistry (mIHC) was employed to identify the specific cells where Lsm2 gene expression is predominant. RNA sequencing and single-nucleus RNA sequencing were conducted to investigate the role of Lsm2 in the pathogenesis of COPD.

RESULTS

In this study, we found that cigarette smoke extract increases Lsm2 expression, and knocking down Lsm2 in 16HBE cells significantly reduces cell viability in vitro. mIHC showed that Lsm2 is primarily expressed in Club cells. Knockout of Lsm2, either in the lungs or specifically in Club cells, exacerbated lung injury and inflammation caused by cigarette smoke exposure in vivo. Single-nucleus RNA sequencing analysis revealed that Club cell-specific knockout of Lsm2 leads to a reduction in the Club cell population, particularly those expressing Chia1+/Crb1+. This decrease in Club cells subsequently reduces the number of ciliated epithelial cells.

CONCLUSION

Knocking out Lsm2 in Club cells results in a significant decrease in Club cell numbers, which subsequently leads to a reduction in ciliated epithelial cells. This increased lung vulnerability to cigarette smoke and accelerating the progression of COPD. Our findings highlight that Lsm2 is critical to club cell proliferation and its inhibition aggravates COPD progression.

Possible Resolution of Food Allergies Following Tocilizumab-Induced Remission of Juvenile Idiopathic Arthritis

This case report describes a unique instance of a four-year-old Ashkenazi Jewish male with systemic juvenile idiopathic arthritis (JIA) and severe IgE-mediated food allergies who achieved complete remission of both conditions following treatment with tocilizumab, an IL-6 receptor antagonist. The patient initially presented with anaphylactic reactions to peanuts, eggs, and cow's milk, confirmed by positive skin prick tests and elevated specific IgE (sIgE) levels. Systemic JIA symptoms, including daily fever spikes, evanescent rash, and polyarticular arthritis, developed shortly thereafter. After inadequate response to standard therapies, tocilizumab was initiated, resulting in complete remission of JIA symptoms and unexpected resolution of food allergies. Repeat allergological evaluations, including skin prick tests, sIgE levels, and controlled oral food challenges, confirmed sustained tolerance to previously allergenic foods. The dual remission observed in this case suggests that interleukin-6 (IL-6) inhibition may modulate shared immunological pathways underlying autoimmune and allergic diseases. IL-6 is a key cytokine in both conditions, promoting Th17-mediated inflammation in JIA and Th2-mediated allergic responses, including IgE production and mast cell activation. While the spontaneous resolution of food allergies, particularly to milk and eggs, is well-documented in pediatric populations, the resolution of peanut allergy, in this case, is highly unusual and temporally associated with tocilizumab treatment. This case raises the possibility that IL-6 inhibition may play a role in modulating autoimmune and allergic responses, warranting further investigation into the interplay between these pathways.

Distinct inflammatory profiles in mustard lung: A study of sulfur mustard-exposed patients with serious pulmonary complications

Mustard Lung (ML) refers to respiratory complications caused by sulfur mustard (SM) exposure, a chemical warfare agent. This study explores the inflammatory profile of SM-exposed veterans with serious ML, aiming to distinguish it from other respiratory diseases. The aim is also to comprehend the role of inflammatory markers in disease severity. A study was conducted on 257 male SM-exposed veterans and 64 unexposed control subjects. Inflammatory markers in serum and sputum samples were measured using the ELISA technique. Clinical evaluations identified the SM-exposed group as the patients with serious problems. Statistical analyses were conducted to compare groups. SM-exposed veterans exhibited decreased serum levels of IL-1α, IL-8, IL-17, GM-CSF, and NO compared to controls, while other markers did not differ significantly. Intriguingly, inflammatory patterns in ML subgroups, including those resembling Bronchiolitis Obliterans (BO), Chronic Bronchitis (CB), and asthma, differed from the corresponding cases of these diseases as reported in prior literature. Additionally, certain factors demonstrated notable decreases in concentration in severe ML cases compared to controls. The study reveals substantial changes in inflammatory markers in ML patients, highlighting their distinctive profile compared to other respiratory conditions. Despite some similarities with asthma, BO, and CB, the ML shows discernible variations in the levels of most inflammatory markers. Furthermore, the severity of ML impacted the serum levels of specific factors. These findings support the notion of classifying ML as a separate pulmonary condition, distinct from CB, BO, and asthma, opening avenues for further research and tailored treatment strategies.

The potential role of nanobodies in asthma therapy

Asthma is a chronic inflammatory disease of the airways characterized by bronchoconstriction, airway hyperresponsiveness, and mucus production. The pathophysiology of asthma involves a complex interplay of immune cells and mediators, including cytokines, chemokines, and other inflammatory molecules. Despite advances in asthma management, many patients continue to experience symptoms due to the limitations of current therapies. Monoclonal antibodies (mAbs) targeting specific inflammatory mediators have improved treatment outcomes for some patients, but challenges such as poor tissue penetration and high costs remain. Nanobodies (Nbs), a novel class of single-domain antibodies, offer a promising alternative due to their small size, stability, and potential for enhanced tissue penetration. This review discusses the key mediators involved in asthma, challenges in current treatments, and the potential of Nbs as a new therapeutic strategy. We also explore current studies and innovations in nanobody technology.

Genetic evidence for the causal effects of air pollution on the risk of respiratory diseases

BACKGROUND

Epidemiological studies have consistently demonstrated a robust association between long-term exposure to air pollutants and respiratory diseases. However, establishing causal relationships remains challenging due to residual confounding in observational studies. In this study, Mendelian randomization (MR) analysis was used to explore the causal and epigenetic relationships between various air pollutants and common respiratory diseases.

METHODS

We utilized a two-sample Mendelian randomization (TSMR) approach to explore the impact of PM2.5, PM2.5-10, PM10, NO2, and NOX on the incidence of nine respiratory diseases using data from large-scale European GWAS datasets (N = 423,796-456,380 for exposures; N = 162,962-486,484 for outcomes). The primary analytical method was inverse variance weighting (IVW), which explored the exposure-outcome relationship using single nucleotide polymorphisms (SNPs) associated with air pollution. Sensitivity analyses, including MR-Egger regression and leave-one-out analyses, were employed to ensure result consistency. Multivariate MR (MVMR) was performed to adjust for potential smoking-related confounders, such as cigarettes per day, household smoking, exposure to tobacco smoke at home, ever smoked, second-hand smoke, smoking initiation, and age at smoking initiation, as well as the independent effects of each air pollutant. Additionally, methylation and enrichment analyses were conducted to further elucidate the potential effects of air pollution on respiratory diseases.

RESULTS

TSMR analysis revealed that exposure to PM2.5 increased the risk of early-onset chronic obstructive pulmonary disease (COPD), pneumonia, pulmonary embolism and lung cancer. PM2.5-10 exposure was associated with an increased risk of lung cancer, while PM10 exposure increased the risk of pneumonia and bronchiectasis. NO2 exposure was associated with increased risks of lung cancer and adult asthma. Importantly, these associations remained robust even after controlling for potential tobacco-related confounders in the MVMR analyses. In the MVMR analysis adjusting for other pollutants, significant associations persisted between PM2.5 and early-onset COPD, and between PM10 and pneumonia. Genetic co-localization analyses confirmed that methylation of PM2.5-associated CpG loci (cg11386376 near c1orf175, cg11846064 near rfx2, cg18612040 near rptor, and cg19765378 near c7orf50) was associated with an increased risk of early-onset COPD. Finally, SNPs significantly associated with exposure and outcome were selected for enrichment analysis.

CONCLUSIONS

Our findings suggest that exposure to air pollutants may play a causal role in the development of respiratory diseases, with a potential role of epigenomic modifications emphasized. Strengthening comprehensive air pollution regulations by relevant authorities could potentially mitigate the risk of these diseases.

Association between chronic respiratory diseases and frailty in Chinese elderly: a population-based longitudinal study

BACKGROUND

Chronic respiratory diseases (CRDs) have been shown to be associated with frailty, but these findings have not yet reached a consensus. The aim of this study was to investigate the association between CRDs and frailty in the elderly using a nationally representative data from China.

METHODS

Data from the China Health and Retirement Longitudinal Study (CHARLS) were analysed, including 3309 frailty-free participants followed for three waves from 2011. Frailty was assessed using the physical frailty phenotype scale, and CRDs were conformed by self-reported physician diagnoses. Cox proportional hazard models were used to examine the association between baseline CRDs and subsequent frailty.

RESULTS

Among participants (mean age 67.07 years, 51.53% male), 497 (15.02%) had CRDs. During a mean follow-up of 46 months, 273 (8.25%) participants developed frailty. The incidence rate of frailty was significantly higher in the CRDs group (37.17% per 1000 person-years vs 18.41% per 1000 person-years, p<0.01). Adjusted for covariables, participants with CRDs had a 44% higher risk of developing frailty (HR = 1.44, 95% CI: 1.08 to 1.91). Specifically, asthma only (HR=1.89, 95% CI: 1.07 to 3.33) and asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO) (HR=1.79, 95% CI: 1.19 to 2.69) were associated with a higher risk of frailty among the elderly, while COPD only was not (HR=1.11, 95% CI: 0.73 to 1.65).

CONCLUSION

This study shows a significant association between CRDs, particularly asthma only and ACO, and frailty in the elderly. We need to pay attention to the frailty status of CRDs patients and consider routine screening among them in both clinical practice and community settings. Active treatment and control of CRDs are necessary to avoid frailty caused by primary lung disease progression or exacerbation.

Molecular mechanisms and clinical impact of biologic therapies in severe asthma

Severe asthma is a critical condition for patients with asthma, characterized by frequent exacerbations, decreased pulmonary function, and unstable symptoms related to asthma. Consequently, the administration of systemic corticosteroids, which cause secondary damage because of their adverse effects, is considered. Recently, several types of molecular-targeted biological therapies have become available for patients with severe asthma, and they have a capacity to improve the pathophysiology of severe asthma. However, several clinical reports indicate that the effects differ depending on the biological targets of asthma in individual patients. In this review, the molecular mechanisms and clinical impact of biologic therapies in severe asthma are described. In addition, molecules targeted by possible future biologics are also addressed. Better understanding of the mechanistic basis for the role of biologics in severe asthma could lead to new therapeutic options for these patients.

Cytokines reprogram airway sensory neurons in asthma

Nociceptor neurons play a crucial role in maintaining the body's homeostasis by detecting and responding to potential environmental dangers. However, this function can be detrimental during allergic reactions, as vagal nociceptors contribute to immune cell infiltration, bronchial hypersensitivity, and mucus imbalance in addition to causing pain and coughing. Despite this, the specific mechanisms by which nociceptors acquire pro-inflammatory characteristics during allergic reactions are not yet fully understood. In this study, we investigate the changes in the molecular profile of airway nociceptor neurons during allergic airway inflammation and identify the signals driving such reprogramming. Using retrograde tracing and lineage reporting, we identify a specific class of inflammatory vagal nociceptor neurons that exclusively innervate the airways. In the ovalbumin mouse model of allergic airway inflammation, these neurons undergo significant reprogramming characterized by the upregulation of the neuropeptide Y (NPY) receptor Npy1r. A screening of cytokines and neurotrophins reveals that interleukin 1β (IL-1β), IL-13, and brain-derived neurotrophic factor (BDNF) drive part of this reprogramming. IL-13 triggers Npy1r overexpression in nociceptors via the JAK/STAT6 pathway. In parallel, NPY is released into the bronchoalveolar fluid of asthmatic mice, which limits the excitability of nociceptor neurons. Single-cell RNA sequencing of lung immune cells reveals that a cell-specific knockout of NPY1R in nociceptor neurons in asthmatic mice altered T cell infiltration. Opposite findings are observed in asthmatic mice in which nociceptor neurons are chemically ablated. In summary, allergic airway inflammation reprograms airway nociceptor neurons to acquire a pro-inflammatory phenotype, while a compensatory mechanism involving NPY1R limits the activity of nociceptor neurons.

Association Between Oxidative Potential of Particulate Matter Collected by Personal Samplers and Systemic Inflammation Among Asthmatic and Non-Asthmatic Adults

With the rationale that the oxidative potential of particulate matter (PM-OP) may induce oxidative stress and inflammation, we conducted the ASTHMA-FENOP study in which 44 asthmatic patients and 37 matched controls wore a personal sampler for 24 h, allowing the collection of fine and coarse PM fractions separately, to determine PM-OP by the dithiothreitol (DTT) and ascorbic acid (AA) methods. The levels of Interleukin 6 (IL-6) and the IL-6/IL-10 ratio, as indicators of pro- and anti-inflammatory statuses, were determined by calculating the mean differences (MDs), odds ratios (ORs) and p-trends adjusted for sex, age, study level and body mass index. Positive associations for IL-6 levels in the form of adjusted MDs and ORs were obtained for all PM-OP metrics, reaching statistical significance for both OP-DTT and OP-AA in the fine fraction, with adjusted OR = 5.66; 95%CI (1.46 to 21.92) and 3.32; 95%CI (1.07 to 10.35), respectively, along with statistically significant dose-response patterns when restricting to asthma and adjusted also for clinical variables (adjusted p-trend = 0.029 and 0.01). Similar or stronger associations and dose-response patterns were found for the IL-6/IL-10 ratio. In conclusion, our findings on the effect of PM-OP on systemic inflammation support that asthma is a heterogeneous disease at the molecular level, with PM-OP potentially playing an important role.

Network Pharmacology and Molecular Docking Reveal Anti-Asthmatic Potential of Zephyranthes rosea Lindl. in an Ovalbumin-Induced Asthma Model

Background: This study aimed to evaluate the anti-inflammatory effects of a Zephyranthes rosea in an ovalbumin-induced asthma model. Methods: Allergic asthma was induced in mice via intraperitoneal injection, followed by intranasal ovalbumin challenge. Methanolic extract of Z. rosea bulb was orally administered to asthmatic mice for 14 days. Hematological parameters for bronchoalveolar lavage fluid (BALF) and blood were analyzed. The mRNA expression levels of interleukins and transforming growth factor beta (TGF-β1) in lung tissues were determined using reverse transcriptase-polymerase chain reaction (RT-PCR). Network pharmacology analysis was used to find possible Z. rosea targets. After building a protein-protein interaction network to find hub genes, GO and KEGG enrichment analyses were carried out to determine the potential mechanism. In silico analysis was performed by Molecular Operating Environment. Results: GC-MS analysis of Z. rosea extract detected major classes of phytochemicals. Hematological parameters in blood and BALF from Z. rosea extract-treated animals were significantly reduced in a dose-dependent fashion. Histopathology revealed that Z. rosea bulb had an ameliorative effect on lung tissues. Moreover, treatment with Z. rosea bulb extract significantly restored the normal levels of IL-4, IL-6, IL-1β, IL-10, IL-13, and TGF-β1 in allergic asthmatic mice compared to the diseased group. In silico analysis, particularly of the binding affinities of Z. rosea bulb phytoconstituents for IL6, AKT1, and Src, supported in vivo results. Conclusions: These findings indicated that Z. rosea bulb extract significantly ameliorates cellular and molecular biomarkers of bronchial inflammation and could be a potential candidate for treating allergic asthma.

House dust mite allergen Der f 2 drives IL-6 and GM-CSF expression in airway epithelial cells via p38 MAPK/NF-κB signaling

OBJECTIVE

Der f 2, a major allergen derived from Dermatophagoides farinae, is a leading cause of allergic asthma. IL-6 and GM-CSF play essential roles in the exacerbation of asthma. However, the mechanical act by which Der f 2 mediates the expression of IL-6, IL-8, and GM-CSF in airway epithelial cells remains incompletely elucidated. Herein, we aimed to explore the effect of Der f 2 on IL-6 and GM-CSF expression in the human airway epithelial cell BEAS-2B and A549.

METHODS

Recombinant Der f 2 (rDf2) was acquired using Pichia pastoris. BEAS-2B and A549 cells were used as cell model. The expression of genes and proteins and the involvement of the signaling cascade were assessed using RT-PCR, quantitative real-time PCR (qPCR), Western blotting, and ELISA, respectively.

RESULTS

Our findings showed that rDf2 significantly induced mRNA expression and protein production of IL-6 and GM-CSF in BEAS-2B and A549 cells. In contrast, rDf2 did not influence IL-8 expression or production in both cells. Mechanistic studies revealed that rDf2 triggered activation of the p38 MAPK and JNK. Inhibition of p38, but not JNK, significantly attenuated rDf2-induced IL-6 and GM-CSF expression and production.

CONCLUSION

This study demonstrates that Der f 2 promotes the expression and production of the pro-inflammatory cytokines IL-6 and GM-CSF in airway epithelial cells via activation of the p38 signaling pathway. These findings provide insights into the molecular mechanisms that Der f 2 may exacerbate airway inflammation.

Rap1A Modulates Store-Operated Calcium Entry in the Lung Endothelium: A Novel Mechanism Controlling NFAT-Mediated Vascular Inflammation and Permeability

BACKGROUND

Store-operated calcium entry mediated by STIM (stromal interaction molecule)-1-Orai1 (calcium release-activated calcium modulator 1) is essential in endothelial cell (EC) functions, affecting signaling, NFAT (nuclear factor for activated T cells)-induced transcription, and metabolic programs. While the small GTPase Rap1 (Ras-proximate-1) isoforms, including the predominant Rap1B, are known for their role in cadherin-mediated adhesion, EC deletion of Rap1A after birth uniquely disrupts lung endothelial barrier function. Here, we elucidate the specific mechanisms by which Rap1A modulates lung vascular integrity and inflammation.

METHODS

The role of EC Rap1A in lung inflammation and permeability was examined using in vitro and in vivo approaches.

RESULTS

We explored Ca2+ signaling in human ECs following siRNA-mediated knockdown of Rap1A or Rap1B. Rap1A knockdown, unlike Rap1B, significantly increased store-operated calcium entry in response to a GPCR (G-protein-coupled receptor) agonist, ATP (500 µmol/L), or thapsigargin (250 nmol/L). This enhancement was attenuated by Orai1 channel blockers 10 μmol/L BTP2 (N-[4-[3,5-bis(trifluoromethyl)-1H-pyrazol-1-yl]phenyl]-4-methyl-1,2,3-thiadiazole-5-carboxamide), 10 μmol/L GSK-7975A, and 5 μmol/L Gd3+. Whole-cell patch clamp measurements revealed enhanced Ca2+ release-activated Ca2+ current density in siRap1A ECs. Rap1A depletion in ECs led to increased NFAT1 nuclear translocation and activity and elevated levels of proinflammatory cytokines (CXCL1 [C-X-C motif chemokine ligand 1], CXCL11 [C-X-C motif chemokine 11], CCL5 [chemokine (C-C motif) ligand 5], and IL-6 [interleukin-6]). Notably, reducing Orai1 expression in siRap1A ECs normalized store-operated calcium entry, NFAT activity, and endothelial hyperpermeability in vitro. EC-specific Rap1A knockout (Rap1AiΔEC) mice displayed an inflammatory lung phenotype with increased lung permeability and inflammation markers, along with higher Orai1 expression. Delivery of siRNA against Orai1 to lung endothelium using lipid nanoparticles effectively normalized Orai1 levels in lung ECs, consequently reducing hyperpermeability and inflammation in Rap1AiΔEC mice.

CONCLUSIONS

Our findings uncover a novel role of Rap1A in regulating Orai1-mediated Ca2+ entry and expression, crucial for NFAT-mediated transcription and endothelial inflammation. This study distinguishes the unique function of Rap1A from that of the predominant Rap1B isoform and highlights the importance of normalizing Orai1 expression in maintaining lung vascular integrity and modulating endothelial functions.

Maternal atopic conditions and autism spectrum disorder: a systematic review

Autism spectrum disorder (ASD) is a disabling neurodevelopmental condition with complex etiology. Emerging evidence has pointed to maternal atopy as a possible risk factor. It is hypothesized that maternal atopic disease during pregnancy can lead to increased levels of inflammatory cytokines in fetal circulation via placental transfer or increased production. These cytokines can then pass through the immature blood-brain barrier, causing aberrant neurodevelopment via mechanisms including premature microglial activation. The objective of this study is to systematically review observational studies that investigate whether a maternal history of atopic disease (asthma, allergy, or eczema/atopic dermatitis) is associated with a diagnosis of ASD in offspring. A search was conducted in Ovid MEDLINE, PsycINFO, and Embase databases for relevant articles up to November 2021; this was later updated in January 2022. Observational studies published in peer-reviewed journals were included. Data were synthesized and qualitatively analyzed according to the specific atopic condition. Quality assessment was done using the Newcastle-Ottawa Scale. Nine articles were identified, with all including asthma as an exposure, alongside four each for allergy and eczema. Findings were inconsistent regarding the association between a maternal diagnosis of either asthma, allergy, or eczema, and ASD in offspring, with variations in methodology contributing to the inconclusiveness. More consistent associations were demonstrated regarding maternal asthma that was treated or diagnosed during pregnancy. Evidence suggests that symptomatic maternal asthma during pregnancy could be associated with ASD in offspring, underscoring the importance of effective management of atopic conditions during pregnancy. Further research is needed, particularly longitudinal studies that use gold-standard assessment tools and correlate clinical outcomes with laboratory and treatment data.PROSPERO Registration Number and Date: CRD42018116656, 26.11.2018.

Exploring potential therapeutic targets for asthma: a proteome-wide Mendelian randomization analysis

BACKGROUND

Asthma poses a significant global health challenge, characterized by high rates of morbidity and mortality. Despite available treatments, many severe asthma patients remain poorly managed, highlighting the need for novel therapeutic strategies. This study aims to identify potential drug targets for asthma by examining the influence of circulating plasma proteins on asthma risk.

METHODS

This study employs summary-data-based Mendelian randomization (MR) and two-sample MR methods to investigate the association between 2940 plasma proteins from the UK Biobank study and asthma. The analysis includes discovery (FinnGen cohort) and replication (GERA cohort) phases, with Bayesian colocalization used to validate the relationships between proteins and asthma. Furthermore, protein-protein interaction and druggability assessments were conducted on high-evidence strength protein biomarkers, and candidate drug prediction and molecular docking were performed for proteins without targeted drugs. Given the complexity of asthma pathogenesis, the study also explores the relationships between plasma proteins and asthma-related endpoints (e.g., obesity-related asthma, infection-related asthma, childhood asthma) to identify potential therapeutic targets for different subtypes.

RESULTS

In the discovery cohort, 75 plasma proteins were associated with asthma, including IL1RAP, IL1RL1, IL6, CXCL5, and CXCL8. Additionally, 6 proteins (IL4R, LTB, CASP8, MAX, PCDH12, and SCLY) were validated through co-localization analysis and validation cohort. The assessment of drug targetability revealed potential drug targets for IL4R, CASP8, and SCLY, while candidate drugs were predicted for LTB and MAX proteins. MAX exhibited strong binding affinity with multiple small molecules indicating a highly stable interaction and significant druggability potential. Analysis of the 75 proteins with 9 asthma-related endpoints highlighted promising targets such as DOK2, ITGAM, CA1, BTN2A1, and GZMB.

CONCLUSION

These findings elucidate the link between asthma, its related endpoints, and plasma proteins, advancing our understanding of molecular pathogenesis and treatment strategies. The discovery of potential therapeutic targets offers new insights into asthma drug target research.

Effects of simulated smoke condensate generated from combustion of selected military burn pit contents on human airway epithelial cells

BACKGROUND

Exposure to military burn pit smoke during deployment is associated with different respiratory and non-respiratory diseases. However, information linking smoke exposure to human pulmonary health is lacking. This study examined the effects of simulated burn pit smoke condensates on human airway epithelial cells (HAECs) from twelve donors (smokers/non-smokers, biological female/male) cultured at an air-liquid interface and exposed to condensates from three simulated burn pit waste materials (cardboard, plywood, and plastic) incinerated at two combustion conditions: smoldering and flaming. Cellular gene expression was analyzed using bulk RNA sequencing, and basolateral media cytokine levels were assessed using multiplex immunoassay.

RESULTS

Flaming smoke condensates caused more significant differentially expressed genes (DEGs) with plywood flaming smoke being the most potent in altering gene expression and modulating cytokine release. Cardboard and plywood flaming condensates primarily activated detoxification pathways, whereas plastic flaming affected genes related to anti-microbial and inflammatory responses. Correlation analysis between smoke condensate chemicals and gene expression to understand the underlying mechanism revealed crucial role of oxygenated polycyclic aromatic hydrocarbons (PAHs) and aluminum, molybdenum, and silicon elements; IL6 expression was positively correlated with most PAHs. Stratification of data based on HAEC donor demographics suggests that these affect gene expression changes. Enrichment analysis indicated similarity with several deployment-related presumptive and reported diseases, including asthma, emphysema, and cancer of different organs.

CONCLUSIONS

This study highlights that simulated burn pit smoke exposure of HAECs causes gene expression changes indicative of deployment-related diseases with more pronounced effects seen in smokers and females. Future studies are needed to further characterize how sex and smoking status affect deployment-related diseases.

Esketamine mitigates mechanical ventilation-induced lung injury in chronic obstructive pulmonary disease rats via inhibition of the MAPK/NF-κB signaling pathway and reduction of oxidative stress

PURPOSE

To investigate esketamine's impact on inflammation and oxidative stress in ventilated chronic obstructive pulmonary disease (COPD) rats, examining its regulatory mechanisms.

METHODS

Rats were divided into four groups: control group (Con), COPD model group (M), COPD model with saline treatment group (M+S), and COPD model with esketamine treatment group (M+K), with 12 rats in each group. After two months, all rats underwent anesthesia and mechanical ventilation. Group M+K received 5 mg/kg esketamine intravenously, while Group M+S received the same volume of saline. Lung tissues were collected for analysis two hours later, including airway peak pressure, wet-to-dry(W/D) ratio, lung permeability index(LPI), hematoxylin and eosin(H&E) staining, and transmission electron microscopy(TEM). Tumor necrosis factor-alpha(TNF-α), interleukin-6(IL-6), interleukin-8(IL-8), and interleukin-10(IL-10) levels were determined by enzyme-linked immunosorbent assay(ELISA); phosphorylated Nuclear Factor Kappa B(p-NF-κB), mitogen-activated protein kinase 14(p38), phosphorylated p38 (p-p38), c-Jun N-terminal kinase(JNK), and phosphorylated JNK (p-JNK) expressions by Western blotting and immunohistochemistry; and malondialdehyde(MDA), myeloperoxidase(MPO), and superoxide dismutase(SOD) levels were also measured by corresponding biochemical assays.

RESULTS

Lung specimens from groups M, M+S, and M+K manifested hallmark histopathological features of COPD. Compared with group Con, group M displayed increased peak airway pressure, W/D ratio, and LPI. In group M+K, compared with group M, esketamine significantly reduced the W/D ratio, LPI, and concentrations of pro-inflammatory cytokines TNF-α, IL-6, and IL-8 while concurrently elevating IL-10 levels. Furthermore, the treatment attenuated the activation of the NF-κB and MAPK pathways, indicated by decreased levels of p-NF-κB, p-p38, and p-JNK.Additionally, compared to group M, group M+K showed decreased MDA and MPO levels and increased SOD levels in lung tissue.

CONCLUSION

Esketamine attenuates mechanical ventilation-induced lung injury in COPD rat models by inhibiting the MAPK/NF-κB signaling pathway and reducing oxidative stress.

Cytokines reprogram airway sensory neurons in asthma

Nociceptor neurons play a crucial role in maintaining the body's homeostasis by detecting and responding to potential dangers in the environment. However, this function can be detrimental during allergic reactions, since vagal nociceptors can contribute to immune cell infiltration, bronchial hypersensitivity, and mucus imbalance, in addition to causing pain and coughing. Despite this, the specific mechanisms by which nociceptors acquire pro-inflammatory characteristics during allergic reactions are not yet fully understood. In this study, we aimed to investigate the molecular profile of airway nociceptor neurons during allergic airway inflammation and identify the signals driving such reprogramming. Using retrograde tracing and lineage reporting, we identified a unique class of inflammatory vagal nociceptor neurons that exclusively innervate the airways. In the ovalbumin mouse model of airway inflammation, these neurons undergo significant reprogramming characterized by the upregulation of the NPY receptor Npy1r. A screening of cytokines and neurotrophins revealed that IL-1β, IL-13 and BDNF drive part of this reprogramming. IL-13 triggered Npy1r overexpression in nociceptors via the JAK/STAT6 pathway. In parallel, sympathetic neurons and macrophages release NPY in the bronchoalveolar fluid of asthmatic mice, which limits the excitability of nociceptor neurons. Single-cell RNA sequencing of lung immune cells has revealed that a cell-specific knockout of Npy1r in nociceptor neurons in asthmatic mice leads to an increase in airway inflammation mediated by T cells. Opposite findings were observed in asthmatic mice in which nociceptor neurons were chemically ablated. In summary, allergic airway inflammation reprograms airway nociceptor neurons to acquire a pro-inflammatory phenotype, while a compensatory mechanism involving NPY1R limits nociceptor neurons' activity.

Loss of JCAD/KIAA1462 Protects the Lung from Acute and Chronic Consequences of Chronic Obstructive Pulmonary Disease

Even with recent advances in pathobiology and treatment options, chronic obstructive pulmonary disease (COPD) remains a major contributor to morbidity and mortality. To develop new ways of combating this disease, breakthroughs in our understanding of its mechanisms are sorely needed. Investigating the involvement of underanalyzed lung cell types, such as endothelial cells (ECs), is one way to further our understanding of COPD. JCAD is a junctional protein in endothelial cells (ECs) arising from the KIAA1462 gene, and a mutation in this gene has been implicated in the risk of developing COPD. In our study, we induced inflammation and emphysema in mice via the global knockout of KIAA1462/JCAD (JCAD-KO) and confirmed it in HPMECs and A549 to examine how the loss of JCAD could affect COPD development. We found that KIAA1462/JCAD loss reduced acute lung inflammation after elastase treatment. Even after 3 weeks of elastase, JCAD-KO mice demonstrated a preserved lung parenchymal structure and vasculature. In vitro, after KIAA1462 expression is silenced, both endothelial and epithelial cells showed alterations in pro-inflammatory gene expression after TNF-α treatment. We concluded that JCAD loss could ameliorate COPD through its anti-inflammatory and anti-angiogenic effects, and that KIAA1462/JCAD could be a novel target for COPD therapy.

Pharmacological profile of dicaffeoylquinic acids and their role in the treatment of respiratory diseases

Dicaffeoylquinic acids (DCQAs) are polyphenolic compounds found in various medicinal plants such as Echinacea species and Hedera helix, whose multi-constituent extracts are used worldwide to treat respiratory diseases. Besides triterpenes, saponins, alkamides, and other constituents, DCQAs are an important group of substances for the pharmacological activity of plant-derived extracts. Therefore, the pharmacological properties of DCQAs have been studied over the last decades, suggesting antioxidative, anti-inflammatory, antimicrobial, hypoglycaemic, cardiovascular protective, neuroprotective, and hepatoprotective effects. However, the beneficial pharmacological profile of DCQAs has not yet been linked to their use in treating respiratory diseases such as acute or even chronic bronchitis. The aim of this review was to assess the potential of DCQAs for respiratory indications based on published in vitro and in vivo pharmacological and pre-clinical data, with particular focus on antioxidative, anti-inflammatory, and respiratory-related effects such as antitussive or antispasmodic properties. A respective literature search revealed a large number of publications on the six DCQA isoforms. Based on this search, a focus was placed on 1,3-, 3,4-, 3,5-, and 4,5-DCQA, as the publications focused mainly on these isomers. Based on the available pre-clinical data, DCQAs trigger cellular mechanisms that are important in the treatment of respiratory diseases such as decreasing NF-κB activation, reducing oxidative stress, or activating the Nrf2 pathway. Taken together, these data suggest an essential role for DCQAs within herbal medicines used for the treatment of respiratory diseases and highlights the need for the identifications of DCQAs as lead substances within such extracts.

In vitro evidence of antioxidant and anti-inflammatory effects of a new nutraceutical formulation explains benefits in a clinical setting of COPD patients

Background and Aim: Increased oxidative stress within the airways is associated to epithelial damage and amplification of inflammatory responses that in turn contribute to Chronic Obstructive Pulmonary Disease (COPD) progression. This study was aimed to identify whether a new formulation of N-acetylcisteine (NAC), carnitine, curcumin and B2 vitamin could counteract oxidative stress and downstream pro-inflammatory events promoted by cigarette smoke extract (CSE) exposure in primary bronchial epithelial cells (PBEC), both submerged/undifferentiated (S-PBEC) and cultured at the air-liquid interface (ALI-PBEC). Methods: PBEC were exposed to CSE with/without the new formulation or NAC alone and ROS production, IL-8 and IL-6 gene expression and protein release were evaluated. Results: CSE increased ROS, IL-8 and IL-6 gene expression and protein release and the new formulation counteracted these effects. NAC alone was not effective on IL-8 and IL-6 release. The effects of a similar nutraceutical formulation were evaluated in COPD patients treated for six months. The results showed that the treatment reduced the concentration of IL-8 in nasal wash and improved quality of life. Conclusion: The tested formulation, exerting antioxidant and anti-inflammatory effects, can preserve airway epithelial homeostasis and improve clinical symptoms in COPD.

A Th2-type immune response and low-grade systemic inflammatory reaction as potential immunotoxic effects in intensive agriculture farmers exposed to pesticides

Pesticides are chemicals widely used in agriculture to keep crops healthy and prevent them from being destroyed by pests, thus contributing to a sustainable food and feed production. However, long-term exposure to these compounds may be harmful to human health as they can affect the function of various organs systems, including the immune system. There is growing evidence that pesticides may increase the risk of developing immune-based diseases and inflammation. This study assessed whether greenhouse farmers occupationally exposed to pesticides presented alterations in immunoregulatory proteins, used as surrogate biomarkers of immune function. The study population consisted of 175 greenhouse workers occupationally exposed to pesticides and 91 non-exposed controls. Serum levels of 27 cytokines, chemokines and growth factors were measured using a magnetic bead-based immunoassay in a subpopulation of 111 greenhouse workers and 79 non-exposed controls. Since analytical determinations were performed in two periods of the same crop season with different use of pesticides (period of high and low pesticide exposure), linear mixed models for repeated measures were used to optimize statistical inference. The increase in IL-13, IL-4 and IL-6 observed in greenhouse workers compared to controls, and in the period of high exposure to pesticides relative to that of low exposure, suggest an altered Th1/Th2 balance towards the Th2 response. This finding points to a type-2 inflammation commonly presented as allergic inflammation, which has often been reported in farm-workers and in which pesticide exposure is considered a risk factor. Furthermore, the increase in IL-1β and VEGF, mediators of inflammation and angiogenesis, may suggest a low-grade systemic inflammation that might underlie chronic pathological conditions linked to pesticide exposure.

Molecular Pathways and Potential Therapeutic Targets of Refractory Asthma

Asthma is a chronic inflammatory lung disease. Refractory asthma poses a significant challenge in management due to its resistance to standard therapies. Key molecular pathways of refractory asthma include T2 inflammation mediated by Th2 and ILC2 cells, eosinophils, and cytokines including IL-4, IL-5, and IL-13. Additionally, non-T2 mechanisms involving neutrophils, macrophages, IL-1, IL-6, and IL-17 mediate a corticosteroid resistant phenotype. Mediators including alarmins (IL-25, IL-33, TSLP) and OX40L have overlap between T2 and non-T2 inflammation and may signify unique pathways of asthma inflammation. Therapies that target these pathways and mediators have proven to be effective in reducing exacerbations and improving lung function in subsets of severe asthma patients. However, there are patients with severe asthma who do not respond to approved therapies. Small molecule inhibitors, such as JAK-inhibitors, and monoclonal antibodies targeting mast cells, IL-1, IL-6, IL-33, TNFα, and OX40L are under investigation for their potential to modulate inflammation involved in refractory asthma. Understanding refractory asthma heterogeneity and identifying mediators involved are essential in developing therapeutic interventions for patients unresponsive to currently approved biologics. Further investigation is needed to develop personalized treatments based on these molecular insights to potentially offer more effective treatments for this complex disease.

The Cytochrome P450 2C8*3 Variant (rs11572080) Is Associated with Improved Asthma Symptom Control in Children and Altered Lipid Mediator Production and Inflammatory Response in Human Bronchial Epithelial Cells

This study investigated an association between the cytochrome P450 (CYP) 2C8*3 polymorphism with asthma symptom control in children and changes in lipid metabolism and pro-inflammatory signaling by human bronchial epithelial cells (HBECs) treated with cigarette smoke condensate (CSC). CYP genes are inherently variable in sequence, and while such variations are known to produce clinically relevant effects on drug pharmacokinetics and pharmacodynamics, the effects on endogenous substrate metabolism and associated physiologic processes are less understood. In this study, CYP2C8*3 was associated with improved asthma symptom control among children: Mean asthma control scores were 3.68 (n = 207) for patients with one or more copies of the CYP2C8*3 allele versus 4.42 (n = 965) for CYP2C8*1/*1 (P = 0.0133). In vitro, CYP2C8*3 was associated with an increase in montelukast 36-hydroxylation and a decrease in linoleic acid metabolism despite lower mRNA and protein expression. Additionally, CYP2C8*3 was associated with reduced mRNA expression of interleukin-6 (IL-6) and C-X-C motif chemokine ligand 8 (CXCL-8) by HBECs in response to CSC, which was replicated using the soluble epoxide hydrolase inhibitor, 12-[[(tricyclo[3.3.1.13,7]dec-1-ylamino)carbonyl]amino]-dodecanoic acid. Interestingly, 9(10)- and 12(13)- dihydroxyoctadecenoic acid, the hydrolyzed metabolites of 9(10)- and 12(13)- epoxyoctadecenoic acid, increased the expression of IL-6 and CXCL-8 mRNA by HBECs. This study reveals previously undocumented effects of the CYP2C8*3 variant on the response of HBECs to exogenous stimuli. SIGNIFICANCE STATEMENT: These findings suggest a role for CYP2C8 in regulating the epoxyoctadecenoic acid:dihydroxyoctadecenoic acid ratio leading to a change in cellular inflammatory responses elicited by environmental stimuli that exacerbate asthma.

Anti-Inflammatory and Anti-Oxidant Properties of N-Acetylcysteine: A Fresh Perspective

N-acetyl-L-cysteine (NAC) was initially introduced as a treatment for mucus reduction and widely used for chronic respiratory conditions associated with mucus overproduction. However, the mechanism of action for NAC extends beyond its mucolytic activity and is complex and multifaceted. Contrary to other mucoactive drugs, NAC has been found to exhibit antioxidant, anti-infective, and anti-inflammatory activity in pre-clinical and clinical reports. These properties have sparked interest in its potential for treating chronic lung diseases, including chronic obstructive pulmonary disease (COPD), bronchiectasis (BE), cystic fibrosis (CF), and idiopathic pulmonary fibrosis (IPF), which are associated with oxidative stress, increased levels of glutathione and inflammation. NAC's anti-inflammatory activity is noteworthy, and it is not solely secondary to its antioxidant capabilities. In ex vivo models of COPD exacerbation, the anti-inflammatory effects have been observed even at very low doses, especially with prolonged treatment. The mechanism involves the inhibition of the activation of NF-kB and neurokinin A production, resulting in a reduction in interleukin-6 production, a cytokine abundantly present in the sputum and breath condensate of patients with COPD and correlates with the number of exacerbations. The unique combination of mucolytic, antioxidant, anti-infective, and anti-inflammatory properties positions NAC as a safe, cost-effective, and efficacious therapy for a plethora of respiratory conditions.

The Role of Exhaled Breath Condensate in Chronic Inflammatory and Neoplastic Diseases of the Respiratory Tract

Asthma and chronic obstructive pulmonary disease (COPD) are among the most common chronic respiratory diseases. Chronic inflammation of the airways leads to an increased production of inflammatory markers by the effector cells of the respiratory tract and lung tissue. These biomarkers allow the assessment of physiological and pathological processes and responses to therapeutic interventions. Lung cancer, which is characterized by high mortality, is one of the most frequently diagnosed cancers worldwide. Current screening methods and tissue biopsies have limitations that highlight the need for rapid diagnosis, patient differentiation, and effective management and monitoring. One promising non-invasive diagnostic method for respiratory diseases is the assessment of exhaled breath condensate (EBC). EBC contains a mixture of volatile and non-volatile biomarkers such as cytokines, leukotrienes, oxidative stress markers, and molecular biomarkers, providing significant information about inflammatory and neoplastic states in the lungs. This article summarizes the research on the application and development of EBC assessment in diagnosing and monitoring respiratory diseases, focusing on asthma, COPD, and lung cancer. The process of collecting condensate, potential issues, and selected groups of markers for detailed disease assessment in the future are discussed. Further research may contribute to the development of more precise and personalized diagnostic and treatment methods.

IL-6 mediates olfactory dysfunction in a mouse model of allergic rhinitis

BACKGROUND

Immune-inflammatory response is a key element in the occurrence and development of olfactory dysfunction (OD) in patients with allergic rhinitis (AR). As one of the core factors in immune-inflammatory responses, interleukin (IL)-6 is closely related to the pathogenesis of allergic diseases. It may also play an important role in OD induced by diseases, such as Sjögren's syndrome and coronavirus disease 2019. However, there is no study has reported its role in OD in AR. Thus, this study aimed to investigate the role of IL-6 in AR-related OD, in an attempt to discover a new target for the prevention and treatment of OD in patients with AR.

METHODS

Differential expression analysis was performed using the public datasets GSE52804 and GSE140454 for AR, and differentially expressed genes (DEGs) were obtained by obtaining the intersection points between these two datasets. IL-6, a common differential factor, was obtained by intersecting the DEGs with the General Olfactory Sensitivity Database (GOSdb) again. A model of AR mice with OD was developed by sensitizing with ovalbumin (OVA) to verify the reliability of IL-6 as a key factor of OD in AR and explore the potential mechanisms. Furthermore, a supernatant and microglia co-culture model of nasal mucosa epithelial cells stimulated by the allergen house dust mite extract Derp1 was established to identify the cellular and molecular mechanisms of IL-6-mediated OD in AR.

RESULTS

The level of IL-6 in the nasal mucosa and olfactory bulb of AR mice with OD significantly increased and showed a positive correlation with the expression of olfactory bulb microglia marker Iba-1 and the severity of OD. In-vitro experiments showed that the level of IL-6 significantly increased in the supernatant after the nasal mucosa epithelial cells were stimulated by Derp1, along with significantly decreased barrier function of the nasal mucosa. The expression levels of neuroinflammatory markers IL-1β and INOS increased after a conditioned culture of microglia with the supernatant including IL-6. Then knockdown (KD) of IL-6R by small interfering RNA (siRNA), the expression of IL-1β and INOS significantly diminished.

CONCLUSION

IL-6 plays a key role in the occurrence and development of OD in AR, which may be related to its effect on olfactory bulb microglia-mediated neuroinflammation.

The role of interleukin-10 receptor alpha (IL10Rα) in Mycobacterium avium subsp. paratuberculosis infection of a mammary epithelial cell line

BACKGROUND

Johne's disease is a chronic wasting disease caused by the bacterium Mycobacterium avium subspecies paratuberculosis (MAP). Johne's disease is highly contagious and MAP infection in dairy cattle can eventually lead to death. With no available treatment for Johne's disease, genetic selection and improvements in management practices could help reduce its prevalence. In a previous study, the gene coding interleukin-10 receptor subunit alpha (IL10Rα) was associated with Johne's disease in dairy cattle. Our objective was to determine how IL10Rα affects the pathogenesis of MAP by examining the effect of a live MAP challenge on a mammary epithelial cell line (MAC-T) that had IL10Rα knocked out using CRISPR/cas9. The wild type and the IL10Rα knockout MAC-T cell lines were exposed to live MAP bacteria for 72 h. Thereafter, mRNA was extracted from infected and uninfected cells. Differentially expressed genes were compared between the wild type and the IL10Rα knockout cell lines. Gene ontology was performed based on the differentially expressed genes to determine which biological pathways were involved.

RESULTS

Immune system processes pathways were targeted to determine the effect of IL10Rα on the response to MAP infection. There was a difference in immune response between the wild type and IL10Rα knockout MAC-T cell lines, and less difference in immune response between infected and not infected IL10Rα knockout MAC-T cells, indicating IL10Rα plays an important role in the progression of MAP infection. Additionally, these comparisons allowed us to identify other genes involved in inflammation-mediated chemokine and cytokine signalling, interleukin signalling and toll-like receptor pathways.

CONCLUSIONS

Identifying differentially expressed genes in wild type and ILR10α knockout MAC-T cells infected with live MAP bacteria provided further evidence that IL10Rα contributes to mounting an immune response to MAP infection and allowed us to identify additional potential candidate genes involved in this process. We found there was a complex immune response during MAP infection that is controlled by many genes.

Distinct Effects of Respiratory Viral Infection Models on miR-149-5p, IL-6 and p63 Expression in BEAS-2B and A549 Epithelial Cells

Respiratory viruses cause airway inflammation, resulting in epithelial injury and repair. miRNAs, including miR-149-5p, regulate different pathological conditions. We aimed to determine how miR-149-5p functions in regulating pro-inflammatory IL-6 and p63, key regulators of airway epithelial wound repair, in response to viral proteins in bronchial (BEAS-2B) and alveolar (A549) epithelial cells. BEAS-2B or A549 cells were incubated with poly (I:C, 0.5 µg/mL) for 48 h or SARS-CoV-2 spike protein-1 or 2 subunit (S1 or S2, 1 μg/mL) for 24 h. miR-149-5p was suppressed in BEAS-2B challenged with poly (I:C), correlating with IL-6 and p63 upregulation. miR-149-5p was down-regulated in A549 stimulated with poly (I:C); IL-6 expression increased, but p63 protein levels were undetectable. miR-149-5p remained unchanged in cells exposed to S1 or S2, while S1 transfection increased IL-6 expression in BEAS-2B cells. Ectopic over-expression of miR-149-5p in BEAS-2B cells suppressed IL-6 and p63 mRNA levels and inhibited poly (I:C)-induced IL-6 and p63 mRNA expressions. miR-149-5p directly suppressed IL-6 mRNA in BEAS-2B cells. Hence, BEAS-2B cells respond differently to poly (I:C), S1 or S2 compared to A549 cells. Thus, miR-149-5p dysregulation may be involved in poly (I:C)-stimulated but not S1- or S2-stimulated increased IL-6 production and p63 expression in BEAS-2B cells.

Burn Pit Smoke Condensate-Mediated Toxicity in Human Airway Epithelial Cells

Burn pits are a method of open-air waste management that was common during military operations in Iraq, Afghanistan, and other regions in Southwest Asia. Veterans returning from deployment have reported respiratory symptoms, potentially from exposure to burn pit smoke, yet comprehensive assessment of such exposure on pulmonary health is lacking. We have previously shown that exposure to condensates from burn pit smoke emissions causes inflammation and cytotoxicity in mice. In this study, we explored the effects of burn pit smoke condensates on human airway epithelial cells (HAECs) to understand their impact on cellular targets in the human lung. HAECs were cultured at the air-liquid interface (ALI) and exposed to burn pit waste smoke condensates (plywood, cardboard, plastic, mixed, and mixed with diesel) generated under smoldering and flaming conditions. Cytotoxicity was evaluated by measuring transepithelial electrical resistance (TEER) and lactate dehydrogenase (LDH) release; toxicity scores (TSs) were quantified for each exposure. Pro-inflammatory cytokine release and modulation of gene expression were examined for cardboard and plastic condensate exposures. Burn pit smoke condensates generated under flaming conditions affected cell viability, with flaming mixed waste and plywood exhibiting the highest toxicity scores. Cardboard and plastic smoke condensates modulated cytokine secretion, with GM-CSF and IL-1β altered in more than one exposure group. Gene expression of detoxifying enzymes (ALDH1A3, ALDH3A1, CYP1A1, CYP1B1, NQO1, etc.), mucins (MUC5AC, MUC5B), and cytokines was affected by several smoke condensates. Particularly, expression of IL6 was elevated following exposure to all burn pit smoke condensates, and polycyclic aromatic hydrocarbon acenaphthene was positively associated with the IL-6 level in the basolateral media of HAECs. These observations demonstrate that exposure to smoke condensates of materials present in burn pits adversely affects HAECs and that aberrant cytokine secretion and altered gene expression profiles following burn pit material smoke exposure could contribute to the development of airway disease.

Preventing CXCL12 elevation helps to reduce acute exacerbation of COPD in individuals co-existing type-2 diabetes: A bioinformatics and clinical pharmacology study

AIMS

To investigate the immunology shared mechanisms underlying chronic obstructive pulmonary disease (COPD) and type 2 diabetes mellitus (T2DM) and examine the impact of anti-diabetic drugs on acute exacerbation of COPD (AECOPD).

METHODS

We analyzed GSE76925, GSE76894, GSE37768, and GSE25724 to identify differentially expressed genes. Hub-genes were identified through protein-protein interaction network analysis and evaluated by the receiver operating characteristic curve. CXCL12 emerged as a robust biomarker, and its correlation with lung function and CD8+ T cells were further quantified and validated. The activated signaling pathways were inferred through Gene set enrichment analysis (GSEA). The retrospective clinical analysis was executed to identify the influence of dipeptidyl peptidase-4 inhibitors (DPP-4i) on CXCL12 and evaluate the drug's efficacy in AECOPD.

RESULTS

The significant up-regulation of CXCL12 expression in patients with two diseases were revealed. CXCL12 exhibited a negative correlation with pulmonary function (r = -0.551, p < 0.05). Consistent with analysis in GSE76925 and GSE76894, the positive correlation between the proportion of CD8+ T cells was demonstrated(r=0.469, p<0.05). GSEA identified "cytokines interaction" as an activated signaling pathway, and the clinical study revealed the correlation between CXCL12 and IL-6 (r=0.668, p<0.05). In patients with COPD and T2DM, DDP-4i treatment exhibited significantly higher serum CXCL12, compared to GLP-1RA. Analysis of 187 COPD patients with T2DM indicated that the DPP-4i group had a higher frequency of AECOPD compared to the GLP-1RA group (OR 1.287, 95%CI [1.018-2.136]).

CONCLUSIONS

CXCL12 may represent a therapeutic target for COPD and T2DM. GLP-1RA treatment may be associated with lower CXCL12 levels and a lower risk of AECOPD compared to DPP-4i treatment.

CLINICAL TRIAL REGISTRATION

China Clinical Trial Registration Center（ChiCTR2200055611）.

A powerful approach to identify replicable variants in genome-wide association studies

Replicability is the cornerstone of modern scientific research. Reliable identifications of genotype-phenotype associations that are significant in multiple genome-wide association studies (GWASs) provide stronger evidence for the findings. Current replicability analysis relies on the independence assumption among single-nucleotide polymorphisms (SNPs) and ignores the linkage disequilibrium (LD) structure. We show that such a strategy may produce either overly liberal or overly conservative results in practice. We develop an efficient method, ReAD, to detect replicable SNPs associated with the phenotype from two GWASs accounting for the LD structure. The local dependence structure of SNPs across two heterogeneous studies is captured by a four-state hidden Markov model (HMM) built on two sequences of p values. By incorporating information from adjacent locations via the HMM, our approach provides more accurate SNP significance rankings. ReAD is scalable, platform independent, and more powerful than existing replicability analysis methods with effective false discovery rate control. Through analysis of datasets from two asthma GWASs and two ulcerative colitis GWASs, we show that ReAD can identify replicable genetic loci that existing methods might otherwise miss.

Traffic-related air pollution in marginalized neighborhoods: a community perspective

OBJECTIVES

Marginalized communities are exposed to higher levels of traffic-related air pollution (TRAP) than the general population. TRAP exposure is linked to pulmonary toxicity, neurotoxicity, and cardiovascular toxicity often through mechanisms of inflammation and oxidative stress. Early life exposure to TRAP is also implicated in higher rates of asthma in these same communities. There is a critical need for additional epidemiological, in vivo, and in vitro studies to define the health risks of TRAP exposure affecting the most vulnerable groups to set strict, protective air pollution standards in these communities.

MATERIALS AND METHODS

A literature review was conducted to summarize recent findings (2010-2024) concerning TRAP exposure and toxic mechanisms that are relevant to the most affected underserved communities.

CONCLUSIONS

Guided by the perspectives of NYC community scientists, this contemporary review of toxicological and epidemiological studies considers how the exposome could lead to disproportionate exposures and health effects in underserved populations.

Fine particulate matter aggravates smoking induced lung injury via NLRP3/caspase-1 pathway in COPD

BACKGROUND

Exposure to noxious particles, including cigarette smoke and fine particulate matter (PM2.5), is a risk factor for chronic obstructive pulmonary disease (COPD) and promotes inflammation and cell death in the lungs. We investigated the combined effects of cigarette smoking and PM2.5 exposure in patients with COPD, mice, and human bronchial epithelial cells.

METHODS

The relationship between PM2.5 exposure and clinical parameters was investigated in patients with COPD based on smoking status. Alveolar destruction, inflammatory cell infiltration, and pro-inflammatory cytokines were monitored in the smoking-exposed emphysema mouse model. To investigate the mechanisms, cell viability and death and pyroptosis-related changes in BEAS-2B cells were assessed following the exposure to cigarette smoke extract (CSE) and PM2.5.

RESULTS

High levels of ambient PM2.5 were more strongly associated with high Saint George's respiratory questionnaire specific for COPD (SGRQ-C) scores in currently smoking patients with COPD. Combined exposure to cigarette smoke and PM2.5 increased mean linear intercept and TUNEL-positive cells in lung tissue, which was associated with increased inflammatory cell infiltration and inflammatory cytokine release in mice. Exposure to a combination of CSE and PM2.5 reduced cell viability and upregulated NLRP3, caspase-1, IL-1β, and IL-18 transcription in BEAS-2B cells. NLRP3 silencing with siRNA reduced pyroptosis and restored cell viability.

CONCLUSIONS

PM2.5 aggravates smoking-induced airway inflammation and cell death via pyroptosis. Clinically, PM2.5 deteriorates quality of life and may worsen prognosis in currently smoking patients with COPD.

Olfactory decline develops in parallel with frailty in older US adults with obstructive lung diseases

BACKGROUND

Frailty is prevalent among older adults with asthma or chronic obstructive pulmonary disease (obstructive lung diseases [OLDs]). Frailty and OLD's co-occurrence is associated with increased hospitalization/mortality. Chemosensory dysfunction is closely connected to both OLD and frailty. We evaluated the utility of olfactory decline as a biomarker of frailty in the setting of OLD.

METHODS

We performed a prospective, longitudinal, nationally representative study of community-dwelling older US adults in the National Social Life, Health and Aging Project, an omnibus in-home survey. Respondents reported a physician's diagnosis of OLD. Decline in odor identification and sensitivity over 5 years and frailty (adapted fried frailty phenotype criteria) were measured using standard tools. Multivariate logistic regressions evaluated the association between OLD status, olfactory decline, and frailty.

RESULTS

We compared individuals with OLD (n = 98; mean age 71.2 years, 59.2% women) and those without OLD (n = 1036; mean age 69.5 years, 58.9% women). Olfactory identification decline was associated with developing frailty over the 5-year follow-up period in individuals with OLD (odds ratio [OR] = 9.1, 95% confidence interval [CI] = 2.1-38.6, p = 0.003). Olfactory decline predicted incidence of frailty in individuals with OLD (identification: OR = 4.8, 95% CI = 1.3-17.5, P = 0.018; sensitivity: OR = 6.1, 95%CI = 1.2-31.0, p = 0.030) but not in those without OLD adjusting for demographics, heavy alcohol use, current smoking, and comorbidity. Results were robust to different thresholds for olfactory decline and frailty development.

CONCLUSIONS

Older adults with OLD who experience olfactory decline face higher odds of developing frailty. Use of olfactory decline as a biomarker to identify frailty could allow earlier intervention and decrease adverse outcomes for high-risk older adults with OLD.

The efficacy of citalopram or escitalopram in patients with asthma and major depressive disorder

BACKGROUND

Major depressive disorder is common in people with asthma. Yet, few studies have evaluated depression treatment in those with asthma.

OBJECTIVE

To explore the relationship between antidepressant use, depressive symptoms, and asthma control, pooled data from 3 randomized trials of either citalopram or escitalopram were assessed.

METHODS

Linear fixed effects and binary logistic regression analyses were conducted with between-subject covariates including treatment group, (original) study, and demographics. The within-subject effect of visit, and a treatment group-visit (between-within) interaction effect, were also evaluated. Analyses were repeated in a high asthma exacerbation subgroup having at least 3 oral corticosteroid bursts in the previous 12 months. Outcomes included the Hamilton rating scale for depression (HAM-D17), the 7-item asthma control questionnaire (ACQ), and oral corticosteroid use (yes or no).

RESULTS

In the pooled sample (n = 255), the antidepressant treatment group exhibited lower HAM-D17 overall (P ≤ .001) and a lower likelihood for oral corticosteroid use (P ≤ .001) relative to the placebo group. In the high-exacerbation subgroup (n = 96), treatment group participants had lower overall asthma control questionnaire (P = .004) and HAM-D17 scores (P ≤ .001), and a lower likelihood of oral corticosteroid use (P = .003), relative to placebo participants. All treatment group interaction effects were not significant.

CONCLUSION

Citalopram or escitalopram exhibited efficacy in reducing depressive symptoms and the need for rescue oral corticosteroids in patients with asthma and major depressive disorder. Future work should determine whether selective serotonin reuptake inhibitors are effective at improving asthma outcomes in those with asthma who are not depressed.

TRIAL REGISTRATION

Clinicaltrials.gov Identifier: NCT00621946 and NCT01324700 (one study was conducted before ClinicalTrials.gov requirements).

Association between interleukin-6-174G/C gene polymorphism and asthma severity: exploring the role of total serum IgE, blood eosinophils, and FeNO as markers of type 2 inflammation

BACKGROUND

While a connection has been established between serum interleukin-6 (IL-6) levels and the IL-6 gene (- 174G/C) polymorphism in allergic diseases such as asthma, its specific association with severe asthma remains unexplored. This study examined the relationship between the IL-6 (- 174G/C) gene polymorphism and mild and severe asthma, focusing on its influence on type 2 inflammation.

METHODS

Our study comprised 98 patients with mild asthma and 116 with severe asthma. Additionally, we recruited 121 healthy participants to serve as controls for comparative analyses. The IL-6 gene (- 174G/C) polymorphism was assessed utilizing the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method.

RESULTS

In our study, the risk of mild asthma exhibited a significant fourfold increase in individuals with the GG genotype pattern compared to healthy controls, yielding an odds ratio (OR) of 4.4 (p < 0.001). Conversely, we found no significant correlation between the IL-6 - 174G/C gene polymorphism and severe asthma when compared to the healthy control group. However, a noteworthy pattern emerged when we compared subgroups of mild and severe asthma. The risk of severe asthma increased fivefold in individuals with the GC polymorphism pattern, with an OR of 4.99 (p < 0.001), while the likelihood of mild asthma showed a similar fourfold increase with the GG polymorphism pattern, OR = 4.4 (p < 0.001). Consequently, we observed a significantly higher frequency of the C allele in patients with severe asthma, whereas the G allele was more prevalent in individuals with mild asthma (p = 0.05). Additionally, the correlation between markers of type 2 inflammation and the dominant model of the IL-6 gene -174G/C polymorphism (CC + CG vs GG) revealed a significant increase in total serum immunoglobulin E (IgE), Blood Eosinophil Counts (BEC), and Fractional Exhaled Nitric Oxide (FeNO) levels in asthmatic patients with the CC + CG gene pattern compared to those with GG, with p-values of 0.04, 0.03, and 0.04, respectively. Furthermore, after adjusting for other risk factors, the likelihood of developing severe asthma increased from fourfold to eightfold, with an OR of 8.12 (p = 0.01) with (CC + CG) gene pattern. Other predictors for severe asthma included older age and childhood-onset disease (OR = 1.13 and 19.19, p < 0.001). Allergic rhinitis (AR) and nasal polyps (NP) also demonstrated a substantial association with an increased risk of severe asthma, with odds ratios of 5 and 32.29 (p = 0.01 and < 0.001), respectively. Additionally, elevated Body Mass Index (BMI), BEC, and FeNO were linked to severe asthma, with ORs of 1.11, 1.00, and 1.04, respectively (p = 0.04, 0.05, and 0.001).

CONCLUSION

This study illuminated the intricate relationship between the IL-6 gene polymorphism, type 2 inflammation markers, and diverse risk factors in shaping asthma severity. As a significant association between the GG polymorphism of the IL-6 gene (- 174G/C) and mild asthma was found, while possessing at least one C allele, whether in a homozygous (CC) or heterozygous (CG) combination, independently predicts the likelihood of severe asthma.

The Effect of Substrate Properties on Cellular Behavior and Nanoparticle Uptake in Human Fibroblasts and Epithelial Cells

The delivery of nanomedicines into cells holds enormous therapeutic potential; however little is known regarding how the extracellular matrix (ECM) can influence cell-nanoparticle (NP) interactions. Changes in ECM organization and composition occur in several pathophysiological states, including fibrosis and tumorigenesis, and may contribute to disease progression. We show that the physical characteristics of cellular substrates, that more closely resemble the ECM in vivo, can influence cell behavior and the subsequent uptake of NPs. Electrospinning was used to create two different substrates made of soft polyurethane (PU) with aligned and non-aligned nanofibers to recapitulate the ECM in two different states. To investigate the impact of cell-substrate interaction, A549 lung epithelial cells and MRC-5 lung fibroblasts were cultured on soft PU membranes with different alignments and compared against stiff tissue culture plastic (TCP)/glass. Both cell types could attach and grow on both PU membranes with no signs of cytotoxicity but with increased cytokine release compared with cells on the TCP. The uptake of silica NPs increased more than three-fold in fibroblasts but not in epithelial cells cultured on both membranes. This study demonstrates that cell-matrix interaction is substrate and cell-type dependent and highlights the importance of considering the ECM and tissue mechanical properties when designing NPs for effective cell targeting and treatment.

Assessment of MMP-9 and clinical characteristics in dogs with tracheal collapse based on cough severity and fluoroscopic findings: a cross-sectional study

BACKGROUND

Tracheal collapse (TC), a common disease in dogs, is characterized by cough; however, little is known about the serum biomarkers that can objectively evaluate the severity of cough in canine TC. Furthermore, studies elucidating the relationship of fluoroscopic characteristics with the severity of cough are lacking. Therefore, this study aimed to evaluate the relationship between cough severity and clinical characteristics, fluoroscopic images, and new serum biomarkers in canine TC.

RESULTS

Fifty-one client-owned dogs diagnosed with TC based on fluoroscopic and clinical signs were enrolled in this study and divided into three groups according to the severity of cough (grade of cough: 0, 1, and 2). Signalments, comorbidities, and fluoroscopic characteristics were compared among the groups retrospectively. The serum matrix metalloproteinase-9 (MMP-9), interleukin-6 (IL-6), surfactant protein-A (SP-A), and syndecan-1 (SDC-1) levels were measured in all groups. No significant differences in age, breed, sex, or clinical history were observed among the groups. Concomitant pharyngeal collapse increased significantly with the severity of cough (p = .031). Based on the fluoroscopic characteristics, the TC grade of the carinal region increased significantly and consistently with the grade of cough (p = .03). The serum MMP-9 level was significantly higher in the grade 2 group than that in the grade 0 group (p = .014). The serum IL-6 level was significantly lower in the grade 1 group than that in the grade 0 group (p = .020). The serum SP-A and SDC-1 levels did not differ significantly among the groups.

CONCLUSIONS

The severity of cough with the progression of TC can be predicted with the fluoroscopic TC grade at the carinal region. MMP-9 may be used as an objective serum biomarker that represents cough severity to understand the pathogenesis.

Edible pueraria lobata-derived exosome-like nanovesicles ameliorate dextran sulfate sodium-induced colitis associated lung inflammation through modulating macrophage polarization

BACKGROUND

Inflammatory bowel diseases (IBD), such as severe colitis, are associated with the development of lung inflammation and tissue damage. Pueraria lobata (P. lobata) plays an essential role in controlling cytokines. However, the exact mechanism of the inflammation response is still unknown.

PURPOSE

To investigate the effects of the P. lobata-derived exosomes-like nanovesicles (PLDENs) on colitis and their role in the lung inflammatory response.

METHODS

In this study, we investigated the effects of PLDENs on the dextran sulfate sodium (DSS)-induced colitis and explored the mechanisms by forming the gut-lung axis. PLDENs were characterized by mass spectrometry-based proteomic analysis.

RESULTS

The results showed that PLDENs had significant preventive effects in DSS-induced colitis and pathological changes in colons in a dose-dependent manner. Simultaneously, the treatment of PLDENs could effectively reduce inflammatory changes in the lung. PLDENs could selectively regulate the composition of gut microbiota.

CONCLUSION

These data suggested that the treatment of PLDENs could 'attenuate DSS-induced colitis and lung inflammation, providing an efficacious supplement for reducing co-morbidities in IBD patients.

The mechanism of Sanzi Yangqin decoction for asthma treatment based on network pharmacology and experimental verification

BACKGROUND

Asthma is a chronic airway inflammatory disease characterized by airway inflammation, mucus hypersecretion, airway hyper-reactivity. Sanzi Yangqin Decoction (SZYQD) is widely prescribed for asthma treatment. Its anti-asthma activities have been reported in animal model, but the exact mechanism and targets of SZYQD in asthma treatment have not been fully elucidated.

METHODS

A network pharmacological approach was used to predict the active components, targets, and signalling pathways of SZYQD in asthma, including potential target prediction, protein‒protein interaction (PPI) network construction and analysis, and Gene Ont (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. The active ingredients were identified from the SZYQD, and were molecular docked according to the results of network pharmacology. A mouse model of asthma induced by ovalbumin (OVA) and lipopolysaccharide (LPS) was constructed to evaluate the therapeutic effect of SZYQD. Furthermore, the effects of SZYQD and its active ingredients were tested in vitro for regulating inflammation and MUC5AC expression (two main pathophysiologic abnormalities of asthma) in macrophages and airway epithelial cells by using Real-time PCR and western blotting.

RESULTS

A total of 28 active ingredients and 111 HUB genes were screened in the relevant databases, including three key ingredients (luteolin, β-carotene, and Sinapine) and nine core target genes (JUN, CTNNB1, IL10, TP53, AKT1, STAT3, TNF, IL6 and EGFR). KEGG and GO analysis indicated that the potential anti-asthmatic mechanisms of SZYQD were related to PI3K-Akt signalling pathway and response to lipopolysaccharide, etc. In the in vivo asthmatic model, our findings demonstrated that SZYQD exerted a protective effect against asthmatic mice induced by OVA and LPS through the inhibition of inflammation and mucus overproduction. Consistently, cell experiments showed that the SZYQD extract or the key active ingredients luteolin significantly decreased lipopolysaccharide (LPS)-induced IL-6 expression and activation of the NF-κB pathway in macrophages. In addition, SZYQD extract or luteolin inhibited activation of the AKT pathway and expression of MUC5AC induced by EGF in airway epithelial cells.

CONCLUSION

The anti-asthmatic mechanism of SZYQD might be associated with inhibiting inflammation and airway mucus hypersecretion by regulating the NF-κB and AKT signalling pathways as predicted by network pharmacology, which provides more evidence for the application of SZYQD in asthma treatment.

Interleukin 31 receptor α promotes smooth muscle cell contraction and airway hyperresponsiveness in asthma

Asthma is a chronic inflammatory airway disease characterized by airway hyperresponsiveness (AHR), inflammation, and goblet cell hyperplasia. Multiple cytokines, including IFNγ, IL-4, and IL-13 are associated with asthma; however, the mechanisms underlying the effects of these cytokines remain unclear. Here, we report a significant increase in the expression of IL-31RA, but not its cognate ligand IL-31, in mouse models of allergic asthma. In support of this, IFNγ, IL-4, and IL-13 upregulated IL-31RA but not IL-31 in both human and mice primary airway smooth muscle cells (ASMC) isolated from the airways of murine and human lungs. Importantly, the loss of IL-31RA attenuated AHR but had no effect on inflammation and goblet cell hyperplasia in mice challenged with allergens or treated with IL-13 or IFNγ. We show that IL-31RA functions as a positive regulator of muscarinic acetylcholine receptor 3 expression, augmenting calcium levels and myosin light chain phosphorylation in human and murine ASMC. These findings identify a role for IL-31RA in AHR that is distinct from airway inflammation and goblet cell hyperplasia in asthma.

An epithelial gene signature of trans-IL-6 signaling defines a subgroup of type 2-low asthma

BACKGROUND

Asthma is stratified into type 2-high and type 2-low inflammatory phenotypes. Limited success has been achieved in developing drugs that target type 2-low inflammation. Previous studies have linked IL-6 signaling to severe asthma. IL-6 cooperates with soluble-IL-6Rα to activate cell signaling in airway epithelium.

OBJECTIVE

We sought to study the role of sIL-6Rα amplified IL-6 signaling in airway epithelium and to develop an IL-6+ sIL-6Rα gene signature that may be used to select asthma patients who potentially respond to anti-IL-6 therapy.

METHODS

Human airway epithelial cells were stimulated with combinations of IL-6, sIL-6Rα, and inhibitors, sgp130 (Olamkicept), and anti-IL-6R (Tocilizumab), to assess effects on pathway activation, epithelial barrier integrity, and gene expression. A gene signature was generated to identify IL-6 high patients using bronchial biopsies and nasal brushes.

RESULTS

Soluble-IL-6Rα amplified the activation of the IL-6 pathway, shown by the increase of STAT3 phosphorylation and stronger gene induction in airway epithelial cells compared to IL-6 alone. Olamkicept and Tocilizumab inhibited the effect of IL-6 + sIL-6Rα on gene expression. We developed an IL-6 + sIL-6Rα gene signature and observed enrichment of this signature in bronchial biopsies but not nasal brushes from asthma patients compared to healthy controls. An IL-6 + sIL-6Rα gene signature score was associated with lower levels of sputum eosinophils in asthma.

CONCLUSION

sIL-6Rα amplifies IL-6 signaling in bronchial epithelial cells. Higher local airway IL-6 + sIL-6Rα signaling is observed in asthma patients with low sputum eosinophils.

Curative potential of Populus ciliata Wall ex. Royle extract against adjuvant-induced arthritis and peripheral neuropathy in Wistar rats

Populus ciliata (PCCR) is traditionally used to treat muscular swelling, inflammation, pain, and fever. The current study was designed to validate the potential of aqueous ethanolic extract of the plant against inflammation, peripheral neuropathy, and pain in arthritic rats. The PCCR was chemically characterized by gas chromatography-mass spectroscopy and high-performance liquid chromatography. In vitro antioxidant, and in vitro anti-inflammatory assays were carried out on PCCR. For anti-arthritic potential, Wistar rats' rear paws were injected with 0.1 ml Complete Freund's Adjuvant using methotrexate (3 mg/kg/week) as standard control. PCCR at 100, 200, and 400 mg/kg was given orally to arthritic rats for 21 days. The PCCR exhibited significant inhibition of bovine serum albumin denaturation (IC-50: 202.1 µg/ml), egg albumin denaturation (IC-50:553.5 mg/ml) and RBC membrane stabilization (IC-50: 122.5 µg/ml) and antioxidant (IC-50 = 49.43 µg/ml) activities. The PCCR notably decreased the paw diameter and increased body weight of treated arthritic animals as equated to diseased control. The treatment notably (p < 0.05-0.0001) decreased malondialdehyde, and increased superoxide dismutase, reduced glutathione, and catalase in the liver and sciatic nerve homogenate in compared to diseased rats. The PCCR treatment remarkably (p < 0.05-0.0001) regulated the levels of nor-adrenaline and serotonin in sciatic nerve in contrast to diseased rats. Treatment with PCCR improved the motor activity, pain, ligament degeneration, and synovial hyperplasia in arthritic rats. Moreover, PCCR significantly (p < 0.01-0.0001) decreased the IL-6 and TNF-α. It is evident from the current study that PCCR had ameliorated polyarthritis and peripheral neuropathy through reduction of inflammatory markers, and improvement of oxidative stress might be due to presence of phenolic acids, flavonoids, phytosterols, and other fatty acids.

High plasma IL-6 levels may enhance the adverse effects of mouse allergen exposure in urban schools on asthma morbidity in children

BACKGROUND

Few data on the relationships between environmental exposures, asthma morbidity, and systemic IL-6 inflammation exist.

OBJECTIVE

We sought to determine whether baseline plasma IL-6 level is associated with increased asthma morbidity in children exposed to mouse allergen in inner-city classrooms.

METHODS

Data from the longitudinal School Inner-City Asthma Studies of 215 children with asthma, aged 4 to 14 years and recruited from urban elementary schools, were analyzed. Given the unknown threshold of IL-6 risk levels and skewness of the distribution, the children were stratified into tertiles as follows: low baseline IL-6 level (<0.013 pg/mL), moderate baseline IL-6 level (0.013-0.302 pg/mL), and high baseline IL-6 level (>0.302 pg/mL). Relationships between plasma IL-6 level and body mass index (BMI) percentile, inflammatory markers, lung function, mouse allergen exposure, and asthma outcomes were assessed.

RESULTS

Cross-sectional analysis demonstrated that increasing IL-6 level was associated with higher BMI percentile (P < .0001), C-reactive protein level (P = .0006), and blood neutrophil count (P = .0024). IL-6 was not associated with type 2 inflammatory markers, including blood eosinophil count, allergic sensitization, or fractional exhaled nitric oxide level. Longitudinal analysis showed that children with high IL-6 levels had a higher number of days with asthma symptoms than did those children with moderate (incidence rate ratio = 1.74 [95% CI = 1.10-2.77]; P = .0187) or low (incidence rate ratio =1.83 [95% CI = 1.21-2.77]; P = .0043) IL-6 levels. Children with high IL-6 levels who were exposed to increasing levels of mouse allergen exhibited lower ratios of FEV1 value to forced vital capacity than did children with moderate IL-6 levels (β = -0.0044 [95% CI = -0.0073 to -0.0015]; pairwise interaction P = .0028) or low IL-6 levels (β = -0.0042 [95% CI = - 0.0070 to -0.0013]; pairwise interaction P = .0039).

CONCLUSIONS

Inner-city children with asthma and high plasma IL-6 levels are more likely to have an increased BMI, elevated C-reactive protein level, elevated blood neutrophil count, and greater asthma symptoms. High IL-6 level appears to increase susceptibility to the effects of classroom exposure to mouse allergen on lung function in urban children.