Prothrombotic State in Asthma Is Related to Increased Levels of Inflammatory Cytokines, IL-6 and TNFα, in Peripheral Blood

Exosomes From IgE-Stimulated Mast Cells Aggravate Asthma-Mediated Atherosclerosis Through circRNA CDR1as-Mediated Endothelial Cell Dysfunction in Mice

BACKGROUND

IgE has been known for mediating endothelial cell dysfunction and mast cell (MC) activation to fuel asthma-aggravated high-fat diet-induced atherosclerosis. However, it remains unclear for the mechanism of asthma-mediated atherosclerosis, especially the potential involvement of IgE in the exacerbation of asthma-mediated atherosclerosis with a standard laboratory diet, and the cross talk between endothelial cells and MCs.

METHODS

Asthma-mediated atherosclerosis mice models under a standard laboratory diet and FcεR1 knock-out mice were used to determine the role of IgE-FcεR1 signaling in asthma-mediated atherosclerosis, which was assessed by Oil Red O staining and immunohistochemistry. Various in vitro assays including nanoparticle tracking analysis and transmission electron microscopy were used to evaluate exosome characteristics. Immunofluorescence and fluorescent in situ hybridization approaches were used to evaluate the effect and mechanism of MC-secreted exosomes encapsulated circular RNA CDR1as (cerebellar degeneration-related 1 antisense) on endothelial cells in vivo and in vitro. Finally, cohort studies examined the plasma CDR1as levels in patients with atherosclerosis with or without allergies.

RESULTS

Asthma mice with a standard laboratory diet showed increased atherosclerotic lesions and inflammatory infiltration depending on IgE-FcεR1 signal. FcεR1 knockout mice and blockage of IgE-FcεR1 signaling with IgE monoclonal antibody, omalizumab, all significantly alleviated asthma-mediated atherosclerosis and vascular inflammatory remodeling. Anti-inflammation with dexamethasone and stabilization of MC with cromolyn partially alleviated atherosclerotic lesions and mitigated the inflammatory infiltration in arteries. Mechanistically, IgE stimulation upregulates MC CDR1as expression in exosomes and upregulates the endothelial cell adhesive factors VCAM-1 (vascular cell adhesion molecule-1) and ICAM-1 (intercellular adhesion molecule-1) via the CDR1as-FUS (fused in sarcoma)-phos-p65 axis. Knockdown of CDR1as in vivo significantly decreased the endothelial adhesion function and mitigated asthma-mediated atherosclerosis. Furthermore, a cohort study indicated higher plasma CDR1as levels in patients with atherosclerosis with allergies than in patients with atherosclerosis and healthy controls.

CONCLUSIONS

Exosomes from IgE-stimulated MCs aggravated atherosclerosis through circular RNA CDR1as-mediated endothelial dysfunction, providing a novel insight into asthma-mediated atherosclerosis and potential diagnostic and therapeutic targets.

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).

Inhalation of Spray-Dried Extract of Salvia rosmarinus Spenn Alleviates Lung Inflammatory, Oxidative, and Remodeling Changes in Asthmatic Rats

INTRODUCTION

For centuries, Salvia rosmarinus Spenn has been applied as folk medicine to cure different diseases due to its anti-inflammatory, antibacterial, antioxidant, antifungal, and antitumor effects. To find bioactive medicinal herbs exerting a protective effect on airway inflammation and remodeling, we assessed the anti-oxidative and anti-inflammatory effects of an aqueous spray-dried extract of Salvia rosmarinus Spenn. (rosemary) in an ovalbumin-induced asthmatic rat model.

METHODS

Rats were randomly divided into normal control (control), asthma, asthma+rosemary extract (RE) (13 mg/kg), asthma+RE (50 mg/kg), and asthma+budesonide groups. After 50 days, animals were anesthetized, and then blood, bronchoalveolar lavage fluid (BALF), and lung tissues were collected for subsequent serological and pathological studies. Histopathology of lung tissues was evaluated by H&E staining. The oxidative stress parameters and airway inflammation factors in BALF and lung tissue were explored.

RESULTS

Using thin layer chromatography, the presence of rosmarinic acid was confirmed in aqueous extract of rosemary. Furthermore, RE markedly decreased immunoglobulin E levels (50 mg/kg; p < 0.001 vs. asthma group) and inflammatory cytokines (50 mg/kg; p < 0.001 vs. asthma group) and increased antioxidant enzymes (50 mg/kg, p < 0.001 vs. asthma group). Furthermore, RE at a concentration of 50 mg/kg obviously reduced the number of inflammatory cells, goblet cells, and pathological changes compared to the asthma group.

CONCLUSION

The results showed that RE administration might prevent or alleviate allergic asthma-related pathological change, probably via antioxidant and anti-inflammatory mechanisms.

Higher systemic immune-inflammation index and systemic inflammation response index levels are associated with stroke prevalence in the asthmatic population: a cross-sectional analysis of the NHANES 1999-2018

Background

Significant evidence suggests that asthma might originate from low-grade systemic inflammation. Previous studies have established a positive association between the systemic immune-inflammation index (SII) and the systemic inflammation response index (SIRI) levels and the risk of stroke. However, it remains unclear whether SII, SIRI and the prevalence of stroke are related in individuals with asthma.

Methods

The present cross-sectional study used data from the National Health and Nutrition Examination Survey (NHANES) conducted between 1999 and 2018. SII was calculated using the following formula: (platelet count × neutrophil count)/lymphocyte count. SIRI was calculated using the following formula: (neutrophil count × monocyte count)/lymphocyte count. The Spearman rank correlation coefficient was used to determine any correlation between SII, SIRI, and the baseline characteristics. Survey-weighted logistic regression was employed to calculate odds ratios (ORs) and 95% confidence intervals (CIs) to determine the association between SII, SIRI, and stroke prevalence. The predictive value of SII and SIRI for stroke prevalence was assessed through receiver operating characteristic (ROC) curve analysis, with the area under the ROC curve (AUC) being indicative of its predictive value. Additionally, clinical models including SIRI, coronary heart disease, hypertension, age, and poverty income ratio were constructed to evaluate their clinical applicability.

Results

Between 1999 and 2018, 5,907 NHANES participants with asthma were identified, of which 199 participants experienced a stroke, while the remaining 5,708 participants had not. Spearman rank correlation analysis indicated that neither SII nor SIRI levels exhibited any significant correlation with the baseline characteristics of the participants (r<0.1). ROC curves were used to determine the optimal cut-off values for SII and SIRI levels to classify participants into low- and high-level groups. Higher SII and SIRI levels were associated with a higher prevalence of stroke, with ORs of 1.80 (95% CI, 1.18-2.76) and 2.23 (95% CI, 1.39-3.57), respectively. The predictive value of SIRI (AUC=0.618) for stroke prevalence was superior to that of SII (AUC=0.552). Furthermore, the clinical model demonstrated good predictive value (AUC=0.825), with a sensitivity of 67.1% and specificity of 87.7%.

Conclusion

In asthmatics, higher levels of SII and SIRI significantly increased the prevalence of stroke, with its association being more pronounced in individuals with coexisting obesity and hyperlipidaemia. SII and SIRI are relatively stable novel inflammatory markers in the asthmatic population, with SIRI having a better predictive value for stroke prevalence than SII.

Semi-automated thrombin dynamics applying the ST Genesia thrombin generation assay

Background

The haemostatic balance is an equilibrium of pro- and anticoagulant factors that work synergistically to prevent bleeding and thrombosis. As thrombin is the central enzyme in the coagulation pathway, it is desirable to measure thrombin generation (TG) in order to detect possible bleeding or thrombotic phenotypes, as well as to investigate the capacity of drugs affecting the formation of thrombin. By investigating the underlying processes of TG (i.e., prothrombin conversion and inactivation), additional information is collected about the dynamics of thrombin formation.

Objectives

To obtain reference values for thrombin dynamics (TD) analysis in 112 healthy donors using an automated system for TG.

Methods

TG was measured on the ST Genesia, fibrinogen on the Start, anti-thrombin (AT) on the STA R Max and α₂Macroglobulin (α₂M) with an in-house chromogenic assay.

Results

TG was measured using STG-BleedScreen, STG-ThromboScreen and STG-DrugScreen. The TG data was used as an input for TD analysis, in combination with plasma levels of AT, α₂M and fibrinogen that were 113% (108-118%), 2.6 μM (2.2 μM-3.1 μM) and 2.9 g/L (2.6-3.2 g/L), respectively. The maximum rate of the prothrombinase complex (PCmax) and the total amount of prothrombin converted (PCtot) increased with increasing tissue factor (TF) concentration. PC_tot increased from 902 to 988 nM, whereas PC_max increased from 172 to 508 nM/min. Thrombin (T)-AT and T-α₂M complexes also increased with increasing TF concentration (i.e., from 860 to 955 nM and from 28 to 33 nm, respectively). PC_tot, T-AT and T-α₂M complex formation were strongly inhibited by addition of thrombomodulin (-44%, -43%, and -48%, respectively), whereas PC_max was affected less (-24%). PC_tot, PC_max, T-AT, and T-α₂M were higher in women using oral contraceptives (OC) compared to men/women without OC, and inhibition by thrombomodulin was also significantly less in women on OC (p < 0.05).

Conclusions

TG measured on the ST Genesia can be used as an input for TD analysis. The data obtained can be used as reference values for future clinical studies as the balance between prothrombin conversion and thrombin inactivation has shown to be useful in several clinical settings.

Meta-Analysis of the Association Between Asthma and the Risk of Stroke

Introduction

Asthma and stroke share many risk factors. Previous meta-analysis has indicated that asthma is associated with an increased risk of stroke. However, this study were limited by the small number of articles included and the lack of subgroup analyses of different stroke types and different populations. This meta-analysis aimed to synthesize evidence systematically to investigate the impact of asthma on stroke.

Methods

We searched Medline (via PubMed), Web of Science and EMBASE databases and manually identified eligible studies (inception dates to December 25, 2021) that analyzed the association between asthma and stroke. We conducted quality assessment to evaluate the risk of bias of studies and sensitivity analyses to test the robustness of results.

Results

We included 8 cohort studies and 10 cross-sectional studies comprised 3,011,016 participants. We found patients with asthma had a higher risk of stroke than patients without asthma [relative risk (RR): 1.34, 95% confidence interval (CI): 1.21–1.47]. Moreover, asthma significantly increased the risk of ischemic stroke (RR: 1.25, 95% CI: 1.06–1.47) without increasing the risk of hemorrhagic stroke (RR: 1.08, 95% CI: 0.87–1.34). Asthma increased the risk of stroke in both men (RR: 1.20, 95% CI: 1.10–1.32) and women (RR: 1.29, 95% CI: 1.12–1.48) with no significant difference between the sexes. We also found that patients with inactive asthma, child-onset asthma, or no smoking history did not have an increased risk of stroke.

Conclusions

These results supported the finding that asthma could significantly increase the risk of stroke, but this impact was not consistent in different populations.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=290745, identifier: CRD42021290745.

Increased Oxidative Stress in Asthma-Relation to Inflammatory Blood and Lung Biomarkers and Airway Remodeling Indices

Airway inflammation in asthma is related to increased reactive oxygen species generation, potentially leading to tissue injury and subsequent airway remodeling. We evaluated oxidative stress in peripheral blood from asthmatic subjects (n = 74) and matched controls (n = 65), using recently developed real-time monitoring of the protein hydroperoxide (HP) formation by the coumarin boronic acid (CBA) assay. We also investigated the relation of the systemic oxidative stress response in asthma to disease severity, lung function, airway remodeling indices (lung computed tomography and histology), and blood and bronchoalveolar lavage fluid (BAL) inflammatory biomarkers. We documented enhanced systemic oxidative stress in asthma, reflected by 35% faster and 58% higher cumulative fluorescent product generation in the CBA assay (p < 0.001 for both). The dynamics of HP generation correlated inversely with lung function but not with asthma severity or histological measures of airway remodeling. HP generation was associated positively with inflammatory indices in the blood (e.g., C-reactive protein) and BAL (e.g., interleukin [IL]-6, IL-12p70, and neutrophil count). Bronchial obstruction, thicker airway walls, increased BAL IL-6, and citrullinated histone 3 in systemic circulation independently determined increased HP formation. In conclusion, a real-time CBA assay showed increased systemic HP generation in asthma. In addition, it was associated with inflammatory biomarkers, suggesting that proper disease control can also lead to a decrease in oxidative stress.

The Hydroalcoholic Extract of Nasturtium officinale Reduces Lung Inflammation and Oxidative Stress in an Ovalbumin-Induced Rat Model of Asthma

Background

Asthma is known as a disease that causes breathing problems in children and adults and is also associated with chronic inflammation and oxidative stress of the airways. Nasturtium officinale (NO) possesses a wide range of pharmacological properties, particularly anti-inflammation and antioxidant potentials. Thus, this study for the first time was aimed to investigate anti-inflammatory and antioxidative activities of NO extract (NOE) in an ovalbumin-induced rat model of asthma.

Materials and Methods

Forty-four male Wistar rats were sensitized with ovalbumin (OVA) to induce asthma symptoms. The animals were allocated into five groups: control (C), asthmatic (A), A + NOE (500 mg/kg), NOE (500 mg/kg), and A + dexamethasone (DX, 2.5 mg/kg). After 7 days, blood and tissue samples were taken from the rats. Then, the level of inflammatory markers, oxidative stress parameters, and antioxidant enzymes activity were measured.

Results

The obtained results showed that OVA-sensitive rats significantly increased the levels of pro-inflammatory cytokines IL-1B, TGF-β, and SMA-α compared to the control group (p < 0.05), while treatment with NOE remarkably reduced the SMA-α gene expression compared to the asthma group (p < 0.05). Furthermore, it decreased the expression of IL-1B and TNF-α genes, although it was not statistically significant. The level of glutathione peroxidase (GPX) significantly reduced in A group compared to the C group (p < 0.05), whereas NOE administration significantly increased this marker (p < 0.05). Moreover, NOE attenuated inflammation and alveolar injury in the lungs of OVA-sensitive rat compared to the nontreated A group.

Conclusions

Overall, our findings demonstrated that NOE somewhat is able to reduce airway inflammation by reducing inflammatory and increasing GPX activity. Indeed, further experiments investigating the impact of different extract doses are needed to confirm the antioxidant and anti-inflammatory effects of NOE.

Serum Myeloperoxidase as a Biomarker of Asthma Severity Among Adults: A Case Control Study

Background

The contribution of neutrophils is still indistinct in the inflammatory response of bronchial asthma (BAs). Myeloperoxidase (MPO) is an enzyme released from the primary azurophilic granules of the neutrophils. The study aimed to evaluate the levels of serum MPO as a biomarker for the assessment of the level of asthma control.

Methods

The study participants included 94 asthmatic patients and 86 healthy controls. The identification of asthma severity had assessed using the ''Global Initiative for Asthma guidelines''. Asthmatic adults had divided into three groups: Good (n= 22), partial (n= 30), and poor control (n= 44). Also, patients have been divided again into two groups (treated and untreated) for BAs.

Results

The predicted FEV1% and the peak expiratory flow (PEF/L) of all participants had verified by spirometry. The mean patients' age was 31.9±15.1 year, with a predominance of females. The mean asthma duration was 10.5±8.6 years. Mean spirometric parameters (FEV1 and PEF) were significantly lower among the patients (0.00). Significant higher MPO levels had observed among BAs patients (p-0.00). The MPO levels have not differed significantly with asthma levels and had significant differences with the history of treatment. There was a nonsignificant negative correlation between the mean MPO levels and the spirometry variables among the patients. ROC curves revealed a sensitivity, specificity, accuracy for MPO (80.9%, 72.1%, and 84.3%), respectively to predict asthmatic severity.

Conclusion

There were significantly higher MPO levels compared to healthy controls. Levels of serum MPO had a non-significant positive correlation with levels of asthma control, but a negative non-significant correlation with spirometric results.

The role of human mast cells in allergy and asthma

Mast cells are tissue-inhabiting cells that play an important role in inflammatory diseases of the airway tract. Mast cells arise in the bone marrow as progenitor cells and complete their differentiation in tissues exposed to the external environment, such as the skin and respiratory tract, and are among the first to respond to bacterial and parasitic infections. Mast cells express a variety of receptors that enable them to respond to a wide range of stimulants, including the high-affinity FcεRI receptor. Upon initial contact with an antigen, mast cells are sensitized with IgE to recognize the allergen upon further contact. FcεRI-activated mast cells are known to release histamine and proteases that contribute to asthma symptoms. They release a variety of cytokines and lipid mediators that contribute to immune cell accumulation and tissue remodeling in asthma. Mast cell mediators trigger inflammation and also have a protective effect. This review aims to update the existing knowledge on the mediators released by human FcεRI-activated mast cells, and to unravel their pathological and protective roles in asthma and allergy. In addition, we highlight other diseases that arise from mast cell dysfunction, the therapeutic approaches used to address them, and fill the gaps in our current knowledge. Mast cell mediators not only trigger inflammation but may also have a protective effect. Given the differences between human and animal mast cells, this review focuses on the mediators released by human FcεRI-activated mast cells and the role they play in asthma and allergy.

Thrombin cleaves IL-33 and modulates IL-33-activated allergic lung inflammation

BACKGROUND

Organisms have orchestrated coagulation and immune systems. Although a link between inflammation and haemostasis has been reported in asthma, the interaction mechanism has not been completely elucidated. Here, we investigated the direct link between the mammalian immune and coagulation systems.

METHODS

Mice were administered protease or antigens intranasally to induce airway inflammation with or without thrombin inhibitors treatment. The effects of thrombin and its inhibitors on interleukin (IL)-33 were investigated both in vivo and in vitro. Peripheral blood mononuclear cells (PBMCs) and plasma from asthma patients are collected to verify the correlation between thrombin and group 2 innate lymphocytes (ILC2s).

RESULTS

Low-molecular-weight heparin (LMWH, an indirect inhibitor of thrombin) restrained both papain- and fungus-induced type 2 immune responses in mice by inhibiting IL-33 cleavage. Upon examining the potential thrombin protease consensus sites, we found that IL-33 was directly cleaved by thrombin at specific amino acids (R48 and R106) to generate a mature form of IL-33 with potent biological activity. In addition, we found that bivalirudin TFA (a direct inhibitor of thrombin) inhibited a variety of type 2 inflammatory responses, such as those in house dust mite (HDM)- and ovalbumin (OVA)-mediated pulmonary inflammation models. We found that plasma thrombin-antithrombin complex (TATc) levels in asthma patients were positively associated with the number and function of IL-33-responder group 2 innate lymphocytes (ILC2s) among peripheral blood mononuclear cells (PBMCs) from asthma patients.

CONCLUSION

The data suggested that thrombin inhibitors administration could be effective in treating lung inflammation by regulating ILC2s via IL-33 maturation, indicating that targeting thrombin is a potential way to treat allergic diseases.

Zhike Pingchuan Granule suppresses interleukin (IL)-6 or the medium of M2 macrophages induced apoptosis in human bronchial epithelial cells

The aim of this study was to explore the effects and action mechanism of Zhike Pingchuan Granule in human bronchial epithelial cells induced by IL-6 or the supernatant of M2. Upon IL-6 stimulation at different doses, Cell Counting Kit-8 (CCK8) assay and flow cytometry were, respectively, utilized to detect the cell viability and apoptosis levels of 16-HBE cells. ELISA and Western blot were, respectively, used to analyze the inflammatory markers and JAK2/STAT3 signals. Immunofluorescence assay was performed to identify M0 and M2 cells. As shown in results, ZKPC perturbed the expression of IL-6 inducible genes important for apoptosis, oxidative and inflammatory response, which was enhanced by JAK2 inhibitor. Besides the inhibitory effects on the phosphorylation levels of JAK2/STAT3, ZKPC markedly increased cell viability and reduced apoptosis in human bronchial epithelial cells (16-HBE) cultured in the supernatant of M2 cells. Collectively, ZKPC could inhibit the IL-6-induced JAK/STAT3 signaling cascade, increase cell viability and decrease apoptosis induced by the supernatant of M2. A more comprehensive understanding of the action mechanism of ZKPC on JAK2/STAT3 signaling pathway in human bronchial epithelial cells induced by IL-6 or M2 supernatant will enable ZKPC development in the control of asthma.

Improved diet quality is associated with decreased concentrations of inflammatory markers in adults with uncontrolled asthma

BACKGROUND

Asthma has become one of the major public health challenges, and recent studies show promising clinical benefits of dietary interventions, such as the Dietary Approaches to Stop Hypertension (DASH) diet.

OBJECTIVE

The objective of this study was to examine whether changes in diet quality are associated with changes in inflammatory markers important in asthma pathophysiology.

METHODS

In this exploratory study in patients with poorly controlled asthma participating in a randomized controlled trial of a DASH intervention study, changes in concentrations of a broad panel of serum proteins (51-plex Luminex assay, Affymetrix) were determined, and their relation to diet quality (DASH score) assessed by combining data of both intervention and usual-care control groups. Second, the relation between the serum proteins, other biomarkers of inflammation and nutrition, and Asthma Control Questionnaire (ACQ) was assessed.

RESULTS

During the first 3 mo, diet quality (DASH scores) were inversely associated (P < 0.05, false discovery rate P < 0.09) with serum concentrations of a large number serum proteins, reflecting not only general proinflammatory markers such as IL-1β, transforming growth factor α (TGF-α), and IL-6 (r = -0.31 to -0.39) but also a number of proteins associated with asthmatic conditions, specifically several T-helper (Th) 2 (Th2; r = -0.29 to -0.34) and Th17 (r = -0.4) associated cytokines and growth factors. Monokine induced by gamma/chemokine (C-X-C motif) ligand 9 (CXCL9) (MIG/CXCL9), a T-cell attractant induced by IFN-γ previously linked to asthma exacerbations, appeared to be the marker most consistently associated with DASH diet quality for the entire 6-mo study period (r = -0.40 and -0.30 for 0-3 and 3-6 mo, respectively, and standardized coefficient loadings -0.13 in the partial least squares analyses). Decreases in 19 serum protein concentrations were also correlated with improved asthma control during the 6-mo study period.

CONCLUSIONS

Our data in adult patients with poorly controlled asthma suggest that dietary changes, like the introduction of DASH, may have beneficial effects on reducing inflammatory status. This trial was registered at http://www.clinicaltrials.gov as NCT01725945.

Interactions via α2β1 Cell Integrin May Protect against the Progression of Airway Structural Changes in Asthma

Increased airway wall thickness and remodeling of bronchial mucosa are characteristic of asthma and may arise from altered integrin signaling on airway cells. Here, we analyzed the expression of β₁-subfamily integrins on blood and airway cells (flow cytometry), inflammatory biomarkers in serum and bronchoalveolar lavage, reticular basement membrane (RBM) thickness and collagen deposits in the mucosa (histology), and airway geometry (CT-imaging) in 92 asthma patients (persistent airflow limitation subtype: n = 47) and 36 controls. Persistent airflow limitation was associated with type-2 inflammation, elevated soluble α₂ integrin chain, and changes in the bronchial wall geometry. Both subtypes of asthma showed thicker RBM than control, but collagen deposition and epithelial α₁ and α₂ integrins staining were similar. Type-I collagen accumulation and RBM thickness were inversely related to the epithelial expression of the α₂ integrin chain. Expression of α₂β₁ integrin on T-cells and eosinophils was not altered in asthma. Collagen I deposits were, however, more abundant in patients with lower α₂β₁ integrin on blood and airway CD8⁺ T-cells. Thicker airway walls in CT were associated with lower α₂ integrin chain on blood CD4⁺ T-cells and airway eosinophils. Our data suggest that α₂β₁ integrin on inflammatory and epithelial cells may protect against airway remodeling advancement in asthma.

Asthma and stroke: a narrative review

Asthma is a heterogeneous disease, usually characterized by chronic airway inflammation, bronchial reversible obstruction and hyperresponsiveness to direct or indirect stimuli. It is a severe disease causing approximately half a million deaths every year and thus possessing a significant public health burden. Stroke is the second leading cause of death and a major cause of disability worldwide. Asthma and asthma medications may be a risk factors for developing stroke. Nevertheless, since asthma is associated with a variety of comorbidities, such as cardiovascular, metabolic and respiratory, the increased incidence of stroke in asthma patients may be due to a confounding effect. The purpose of this review is to analyze the complex relationship between asthma and stroke.

Effect of Asthma on Erectile Dysfunction in Rats as Determined by Biological Network Analysis

Background

We explored the effect of asthma on erectile dysfunction (ED) and the effects of the expression of related proteins.

Material/Methods

We used a bioinformatics database to predict the targets and pathways associated with asthma and ED. The rat model of asthma was caused by an ovalbumin solution. The number of erections in 30 min was observed by injecting apomorphine into the neck at a dose of 100 μg/kg. Rats with no erection were regarded as the model group (group B), and the previous random 6 normal rats were regarded as the control group (group A). We used hematoxylin and eosin (HE) to compare the tissue structure of the cavernous body of the penis. Real-time quantitative polymerase chain reaction (RT-qPCR) and western blotting were used to determine the expression levels of insulin (INS), interleukin 6 (IL6), albumin (ALB), tumor necrosis factor (TNF), and vascular endothelial growth factor A (VEGFA) at both the protein and messenger ribonucleic acid (mRNA) levels.

Results

HE staining results show that compared with group A, the blood sinus distribution of the cavernous body in group B was disordered, and the density of endothelial cells and smooth muscle cells decreased significantly. Western blotting and RT-qPCR showed that the levels of IL6, TNF, and VEGFA protein and mRNA in group B were significantly higher (P<0.05) than those in group A. The levels of INS and ALB were not significantly different between the 2 groups.

Conclusions

On the basis of the results, we found that asthma caused pathological changes in the penises of rats and led to reduced erectile function via changes in the expression of IL6, TNF, and VEGFA proteins.

Evidence for Exacerbation-Prone Asthma and Predictive Biomarkers of Exacerbation Frequency

Rationale: Cross-sectional studies suggest an exacerbation-prone asthma (EPA) phenotype and the utility of blood eosinophils and plasma IL-6 as predictive biomarkers.Objectives: To prospectively test for EPA phenotype and utility of baseline blood measures of eosinophils and IL-6 as predictive biomarkers.Methods: Three-year asthma exacerbation data were analyzed in 406 adults in the Severe Asthma Research Program-3. Transition models were used to assess uninformed and informed probabilities of exacerbation in year 3. Binomial regression models were used to assess eosinophils and IL-6 as predictive biomarkers.Measurements and Main Results: Eighty-three participants (21%) had ≥1 exacerbation in each year (EPA) and 168 participants (41%) had no exacerbation in any year (exacerbation-resistant asthma). The uninformed probability of an exacerbation in Year 3 was 40%, but the informed probability increased to 63% with an exacerbation in Year 2 and 82% with an exacerbation in Years 1 and 2. The probability of a Year 3 exacerbation with no Year 1 or 2 exacerbations was 13%. Compared with exacerbation-resistant asthma, EPA was characterized by lower FEV₁ and a higher prevalence of obesity, hypertension, and diabetes. High-plasma IL-6 occurred in EPA, and the incident rate ratio for exacerbation increased 10% for each 1-pg/μl increase in baseline IL-6 level. Although high blood eosinophils did not occur in EPA, the incident rate ratio for exacerbations increased 9% for each 100-cell/μl increase in baseline eosinophil number.Conclusions: Longitudinal analysis confirms an EPA phenotype characterized by features of metabolic dysfunction. Blood measures of IL-6, but not eosinophils, were significantly associated with EPA, and IL-6 and eosinophils predicted exacerbations in the sample as a whole.

Deciphering the coagulation profile through the dynamics of thrombin activity

Thrombosis has proven to be extremely difficult to predict. Measuring the generation of thrombin is a very sensitive method to detect changes in the hemostatic system. We developed a method based on the generation of thrombin to further fingerprint hemostasis, which we have named thrombin dynamics. Via this method we are able to exactly measure the prothrombin conversion and thrombin inactivation, and any change in the coagulation cascade will be reflected in these two processes. In the current study we analyzed the importance of the members of the prothrombin complex on the dynamics of thrombin activation and inactivation. We show that prothrombin conversion is predominantly influenced by factor X and antithrombin, which will provide essential insights in complex thrombosis-related diseases, such as liver cirrhosis and kidney failure.

Citrullinated histone H3, a marker of extracellular trap formation, is increased in blood of stable asthma patients

BACKGROUND

Emerging data indicates that extracellular traps (ETs), structures formed by various immune cell types, may contribute to the pathology of noninfectious inflammatory diseases. Histone hypercitrullination is an important step in ETs formation and citrullinated histone H3 (H3cit) is considered a novel and specific biomarker of that process. In the present study we have evaluated circulating H3cit in stable asthmatics and investigated its relationship with asthma severity, pulmonary function and selected blood and bronchoalveolar lavage (BAL) biomarkers.

METHODS

In 60 white adult stable asthmatics and 50 well-matched controls we measured serum levels of H3cit. In asthmatics we also performed bronchoscopy with BAL. We analyzed blood and BAL biomarkers, including interleukin (IL)-4, IL-5, IL-6, IL-10, IL-12p70, IL-17A and interferon γ. For statistical analysis, Mann-Whitney U-test, χ2 test, one-way ANCOVA, ROC curve analysis and univariate linear regression were applied. Independent determinants of H3cit were established in a multiple linear regression model.

RESULTS

Asthma was characterized by elevated circulating H3cit (17.49 [11.25-22.58] vs. 13.66 [8.66-18.87] ng/ml, p = 0.03). In asthmatics positive associations were demonstrated between serum H3cit and lung function variables, including total lung capacity (TLC) (β = 0.37 [95% CI 0.24-0.50]) and residual volume (β = 0.38 [95% CI 0.25-0.51]). H3cit was increased in asthma patients receiving systemic steroids (p = 0.02), as well as in subjects with BAL eosinophilia above 144 cells/ml (p = 0.02). In asthmatics, but not in controls, circulating H3cit correlated well with number of neutrophils (β = 0.31 [95% CI 0.19-0.44]) and monocytes (β = 0.42 [95% CI 0.29-0.55]) in peripheral blood. Furthermore, BAL macrophages, BAL neutrophils, TLC, high-sensitivity C-reactive protein, Il-12p70 and bronchial obstruction degree were independent determinants of H3cit in a multivariate linear regression model.

CONCLUSIONS

Asthma is characterized by increased circulating H3cit likely related to the enhanced lung ETs formation. Inhibition of ETs might be a therapeutic option in selected asthma phenotypes, such as neutrophilic asthma.

How can we minimise the use of regular oral corticosteroids in asthma?

Options to achieve oral corticosteroid (OCS)-sparing have been triggering increasing interest since the 1970s because of the side-effects of OCSs, and this has now become achievable with biologics. The Société de Pneumologie de Langue Française workshop on OCSs aimed to conduct a comprehensive review of the basics for OCS use in asthma and issue key research questions. Pharmacology and definition of regular use were reviewed by the first working group (WG1). WG2 examined whether regular OCS use is associated with T2 endotype. WG3 reported on the specificities of the paediatric area. Key “research statement proposals” were suggested by WG4. It was found that the benefits of regular OCS use in asthma outside episodes of exacerbations are poorly supported by the existing evidence. However, complete OCS elimination couldn’t be achieved in any available studies for all patients and the panel felt that it was too early to conclude that regular OCS use could be declared criminal. Repeated or prolonged need for OCS beyond 1 g·year⁻¹ should indicate the need for referral to secondary/tertiary care. A strategic sequential plan aiming at reducing overall exposure to OCS in severe asthma was then held as a conclusion of the workshop.

A yearly cumulative OCS dose above 1 g should be considered unacceptable in severe asthma and should make the case for referralhttp://bit.ly/34GAYLX

The relationship of airway structural changes to blood and bronchoalveolar lavage biomarkers, and lung function abnormalities in asthma

BACKGROUND

Airway structural changes are important in asthma pathology and require further investigations.

OBJECTIVE

We sought to evaluate which computed tomography (CT) indices, bronchial histological traits, or blood and bronchoalveolar lavage (BAL) biomarkers correlate best with lung function abnormalities in asthma.

METHODS

In 105 white adult asthmatics (53 with a component of fixed airflow obstruction), we determined airway cross-sectional geometry of two proximal (the right upper lobe apical segmental and the left apicoposterior) and two distal (the right and the left basal posterior) bronchi, quantified the low-attenuation lung area (LAA%), and analysed clusters based on airway CT-metrics. We also performed bronchofiberoscopy with BAL and endobronchial biopsy, assessed blood and BAL biomarkers, including interleukin (IL)-4, IL-5, IL-6, IL-10, IL-12p70, IL-17A, IL-23, interferon (INF)γ and periostin, together with circulating a disintegrin and metalloproteinase domain-containing protein (ADAM)33, and investigated interplays between analysed variables.

RESULTS

Patients with fixed airflow limitation were characterized by lower lumen area and increased wall area and wall thickness ratios in distal airways, accompanied by raised LAA%. They had also higher blood neutrophilia, blood and BAL eosinophilia, increased circulating fibrinogen, periostin, and ADAM33. Blood neutrophilia, serum high density lipoproteins, thyroid-stimulating hormone, and shortened activated partial thromboplastin time were determinants of thicker reticular basement membrane (RBM). BAL eosinophilia was the only positive predictor of collagen I accumulation. Surprisingly, we observed a negative correlation between RBM thickening and collagen I deposit. Cluster analysis based on CT-metrics of the right lower lobe basal posterior bronchus revealed three well-separated clusters similar in age, asthma duration, and BMI, but different in RBM thickness, collagen I accumulation, and inflammatory markers.

CONCLUSIONS AND CLINICAL RELEVANCE

Airway remodelling traits are mainly related to the Th₂ profile, higher circulating ADAM33, and blood neutrophilia. Lung function abnormalities and RBM thickening correlate better with CT-metrics of distal than proximal airways.

Increased activity of lipoprotein-associated phospholipase A2 in non-severe asthma

BACKGROUND

Given increased risk of cardiovascular events in asthma we hypothesized that lipoprotein-associated phospholipase A₂ (Lp-PLA₂), an enzyme involved in atherosclerosis, is associated with proinflammatory and prothrombotic blood alterations in this disease.

METHODS

In 164 adult asthmatics (63 with severe asthma) we measured plasma Lp-PLA₂ activity using the PLAC test. We determined its relations to inflammation and prothrombotic blood alterations.

RESULTS

In asthma, Lp-PLA₂ was inversely related to the age (β = -0.1 [-0.18 to -0.02]) and was lower in women (n = 122 [74%], 205 [182-242] vs. 243 [203-262] nmol/min/ml, p = 0.001). Interestingly, Lp-PLA₂ correlated negatively with the asthma severity score (β = -0.15 [-0.23 to -0.07]), being 10.3% higher in those with non-severe (mild or moderate) asthma (n = 101, 62%) as compared to the severe disease subtype (224 [191-261] vs. 203 [181-229], p = 0.006 after adjustment for potential confounders). Lp-PLA₂ activity was positively related to the levels of low-density lipoprotein (β = 0.1 [0.02-0.18]), triglycerides (β = 0.11 [0.03-0.19]) and glucose (β = 0.1 [0.02-0.18]) and inversely to the tumor necrosis factor α (β = -0.27 [-0.35 to -0.2]), high sensitivity C-reactive protein (β = -0.1 [-0.19 to -0.02]) and fibrinogen (β = -0.12 [-0.21 to -0.03]), as well as prothrombin (β = -0.16 [-0.24 to -0.08]), and parameters describing thrombin generation potential, such as endogenous thrombin potential (β = -0.14 [-0.21 to -0.06]) and peak thrombin generated (β = -0.2 [-0.28 to -0.12]).

CONCLUSIONS

Elevated Lp-PLA₂ activity in non-severe asthmatics suggests increased atherosclerotic risk in this group. Lower Lp-PLA₂ activity accompanied by its inverse relationship to inflammatory or prothrombotic blood biomarkers observed in turn in severe asthmatics might be related to the pathogenesis of more severe asthma phenotype.

Pulmonary Embolism and Severe Asthma: Case Report and Literature Review

Pulmonary embolism is a life-threatening disease. Its development is generally thought to be due to causes collectively known as the Virchow's triad. Chronic inflammations are associated with the activation of coagulation and increased risks of venous thromboembolic events. Asthma is one of the chronic inflammatory diseases associated with procoagulants and antifibrinolytic activities in the airways. Coagulation is activated in patients with asthma with the following steps of pathophysiology: Increased tissue factor expression in various cell types, decreased activity of the anticoagulant protein C system and inhibition of fibrinolysis through over-production of plasminogen activator inhibitor type 1 (PAI-1). Asthma is therefore likely a risk factor for pulmonary embolism, especially in those patients with severe disease conditions together with frequent exacerbation. Here we present a case of severe asthma associated with coagulopathy and complicated by massive pulmonary embolism, presented with typical S1Q3T3 on electrocardiography (ECG) and massive thrombosis on computed tomography angiography, successfully treated with directed catheter thrombolytic therapy.

Ozbek O. Thrombin lag time is increased in children with mild asthma

BACKGROUND

Inflammation and coagulation are closely linked events. Thrombin is the key enzyme in coagulation system and also has roles in inflammation.

OBJECTIVE

The aim of our study was to evaluate thrombin generation in children with mild asthma.

METHODS

Forty-two children with mild asthma and 49 healthy children were included in the study. All patients performed spirometry. Thrombin generation tests (TGT) were performed with a calibrated automated thrombogram (CAT) in children without asthma exacerbation during the last six months. During CAT assay thrombogram curves were obtained. The area under the curve showed endogenous thrombin potentials and indicated the total amount of endogenous thrombin generated; the peak height showed the highest thrombin value, thrombin lag time and time to thrombin peak were measured.

RESULTS

Thrombin lag time was significantly longer in children with asthma (3.98±1.2min) compared to those in the control group (3.29±0.6min) (p<0.01). Children with asthma also had longer thrombin tail time compared to the control group (19.5±8.9min vs. 16.7±2.9min, p=0.02). Thrombin peak was inversely correlated with FEF 25-75 (r=-0.41, p<0.01). Thrombin lag time was inversely correlated with FEF 25-75 (r=-0.39, p<0.01).

CONCLUSION

Inflammation in mild asthma seems to disturb coagulation but this disturbance may not be so strong as to increase thrombin levels and may only affect the initiation phase of thrombin generation.

Identification of key genes and pathways using bioinformatics analysis in septic shock children

Background and hypothesis

Sepsis is still one of the reasons for serious infectious diseases in pediatric intensive care unit patients despite the use of anti-infective therapy and organ support therapy. As it is well-known, the effect of single gene or pathway does not play a role in sepsis. We want to explore the interaction of two more genes or pathways in sepsis patients for future works. We hypothesize that the discovery from the available gene expression data of pediatric sepsis patients could know the process or improve the situation.

Methods and results

The gene expression profile dataset GSE26440 of 98 septic shock samples and 32 normal samples using whole blood-derived RNA samples were generated. A total of 1,108 upregulated and 142 downregulated differentially expressed genes (DEGs) were identified in septic shock children using R software packages. The Gene Ontology (GO) enrichment and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway were analyzed using DAVID software; Gene Set Enrichment Analysis method was also used for enrichment analysis of the DEGs. The protein-protein interaction (PPI) network and the top 10 hub genes construction of the DEGs were constructed via plug-in Molecular Complex Detection and cytoHubba of Cytoscape software. From the PPI network, the top 10 hub genes, which are all upregulated DEGs in the septic shock children, were identified as GAPDH, TNF, EGF, MAPK3, IL-10, TLR4, MAPK14, IL-1β, PIK3CB, and TLR2. Some of them were involved in one or more significant inflammatory pathways, such as the enrichment of tumor necrosis factor (TNF) pathway in the activation of mitogen-activated protein kinase activity, toll-like receptor signaling pathway, nuclear factor-κB signaling pathway, PI3K-Akt signaling pathway, and TNF signaling pathway. These findings support future studies on pediatric septic shock.

Impaired fibrinolysis and lower levels of plasma α2-macroglobulin are associated with an increased risk of severe asthma exacerbations

Recently we have reported that asthma is associated with enhanced plasma thrombin formation, impaired fibrinolysis and platelet activation. In the present study we investigated whether described prothrombotic blood alterations might predispose to thromboembolic events or asthma exacerbations. In 164 adult asthmatics we assessed clinical events during 3-year follow-up and analyzed their associations with measured at baseline prothrombotic blood parameters. Data were obtained from 157 (95.7%) of the asthma patients. We documented 198 severe asthma exacerbations (64/year), which occurred in 53 subjects (34%). These patients were older (p = 0.004), had worse asthma control (p = 0.02) and lower spirometry values (p = 0.01), at baseline. Interestingly, this subgroup had longer clot lysis time (CLT), as well as lower α₂-macroglobulin (p = 0.038 and p = 0.04, respectively, after adjustment for potential confounders). Increased CLT and lower α₂-macroglobulin were demonstrated as independent predictors of asthma exacerbation in multiple regression model. Moreover, we documented two episodes of deep vein thrombosis (1.3%), and eight acute coronary syndromes (5.1%). Patients who experienced thromboembolic events (n = 10, 6.4%, 2.1%/year) had lower α₂-macroglobulin (p = 0.04), without differences in efficiency of fibrinolysis and thrombin generation. Impaired fibrinolysis and lower levels of α₂-macroglobulin might predispose to a higher rate of asthma exacerbations, suggesting new links between disturbed hemostasis and asthma.

Ghrelin Ameliorates Asthma by Inhibiting Endoplasmic Reticulum Stress

BACKGROUND

This study aimed to confirm the ameliorative effect of ghrelin on asthma and investigate its mechanism.

MATERIALS AND METHODS

The murine model of asthma was induced by ovalbumin (OVA) treatment and assessed by histological pathology and airway responsiveness to methacholine. The total and differential leukocytes were counted. Tumor necrosis factor α, interferon γ, interleukin-5 and interleukin-13 levels in bronchoalveolar lavage fluid were quantified by commercial kits. The protein levels in pulmonary tissues were measured by Western blot analysis.

RESULTS

Ghrelin ameliorated the histological pathology and airway hyperresponsiveness in the OVA-induced asthmatic mouse model. Consistently, OVA-increased total and differential leukocytes and levels of tumor necrosis factor α, interferon γ, interleukin-5 and interleukin-13 in bronchoalveolar lavage fluid were significantly attenuated by ghrelin. Ghrelin prevented the increased protein levels of the endoplasmic reticulum stress markers glucose regulated protein 78 and CCAAT/enhancer binding protein homologous protein and reversed the reduced levels of p-Akt in asthmatic mice.

CONCLUSIONS

Ghrelin might prevent endoplasmic reticulum stress activation by stimulating the Akt signaling pathway, which attenuated inflammation and ameliorated asthma in mice. Ghrelin might be a new target for asthma therapy.