Traditional Medicinal Plants Conferring Protection Against Ovalbumin-Induced Asthma in Experimental Animals: A Review

Stigmasterol alleviates airway inflammation in OVA-induced asthmatic mice via inhibiting the TGF-β1/Smad2 and IL-17A signaling pathways

Stigmasterol is a common dietary phytosterol with high nutritional value and physiological activity. In this study, we evaluated the effects of stigmasterol on inflammatory cytokines and the TGF-β1/Smad2 and IL-17A signaling pathway in an ovalbumin (OVA)-induced asthma mouse model. Stigmasterol treatment improved airway remodeling. In addition, it significantly attenuated the symptoms of asthma attacks, reduced the number of macrophages, lymphocytes, neutrophils, and eosinophils in BALF and inflammatory cytokines, including IL-1β, IL-5, IL-6, and IL-13. It further decreased the level of IL-17A in BALF, serum and spleen. Spleen single-cell suspension analysis via flow cytometry showed that IL-17A level was consistent with the results obtained in BALF, serum and spleen. Stigmasterol decreased the protein expression levels of TGF-β, p-Smad2 and IL-17A in the spleen, by increasing the protein expression level of IL-10. After 24 h of co-culture of TGF-β, IL-6 and stigmasterol, the level of IL-17 in CD4+ T cell supernatant was lower relative to levels in the group without stigmasterol. Meanwhile, stigmasterol treatment attenuated the expression level of TGF- β, p-Smad2 and IL-17A proteins in CD4+ T cells and enhanced the expression levels of IL-10 protein. These data suggested that stigmasterol inhibited the TGF-β1/Smad2 and IL-17A signaling pathway to achieve anti-asthmatic effects in the OVA-induced asthma mouse model. Collectively, the results of this study are that stigmasterol has achieved preliminary efficacy in the non-clinical laboratory, further studies are needed to consider the clinical application of stigmasterol.

Ethnopharmacological basis and pharmacodynamics prospectives for folkloric claims of Rosa webbiana wall. Ex. Royle in diarrhea and asthma via In vitro, In vivo and In silico techniques

ETHNOPHARMACOLOGICAL RELEVANCE

Rosa webbiana (Family: Rosaceae) is used by South Asian herbalists to treat gastrointestinal and respiratory disorders.

AIM OF THE STUDY

This research aimed at multiple targets to verify R. webbiana for treating diarrhea and asthma. In vitro, in vivo, and in silico experiments were planned to demonstrate the antispasmodic and bronchodilator potential of R. webbiana.

MATERIALS AND METHODS

The bioactive compounds of R. webbiana were identified and quantified through LC ESI-MS/MS and HPLC. These compounds were predicted for muti-mechanisms of bronchodilator and antispasmodic potential in network pharmacology and molecular docking. In vitro methods (isolated rabbit trachea, bladder, and jejunum tissues) confirmed these multi-mechanisms for antispasmodic and bronchodilator effects. Antiperistalsis, antidiarrheal, and antisecretory experiments were conducted in in-vivo experiments.

RESULTS

The phytochemical analysis indicates the presence of rutin (742.91 μg/g), kaempferol (726.32 μg/g), and quercitrin (688.20 μg/g) in Rw. EtOH. These bioactive compounds in network pharmacology interfere with the pathogenic genes of diarrhea and asthma, which are the members of calcium-mediated signaling pathways and showed the stronger binding affinity towards voltage-gated L-type calcium channels, myosin light chain-kinase, Calcium calmodulin-dependent-kinase, Phosphodiesterase-4, and phosphoinositide phospholipase-C in molecular docking. Rw. EtOH elicited a spasmolytic response in isolated jejunum, trachea, and urine preparations by relaxing K+ (80 mM) and CCh (1 μM) spastic contractions. Additionally, it suppressed calcium concentration-response curves to the right, like verapamil. Like dicyclomine, it caused a rightward parallel shift of the CCh curves, followed by a non-parallel shift at higher concentrations with suppression of the maximal response. Like papaverine, it also caused isoprenaline-induced inhibitory CRCs to shift to the left. Verapamil did not potentiate isoprenaline-induced inhibitory CRCs, although it was more efficacious against K+ (80 mM) than CCh (1 μM)-induced contractions. R. webbiana EtOH extract exhibited complete antiperistalsis (21.55%), antidiarrheal (80.33%), and antisecretory (82.59±0.60) activities in vivo experiments at the dose of 300 mg/kg.

CONCLUSION

Thus, Rw. EtOH modulated multiple pathways, produced calcium antagonistic, anticholinergic, and phosphodiesterase inhibitory actions, and had antidiarrheal and bronchodilator effects.

MAP3K19 Affects TWEAK-Induced Response in Cultured Bronchial Epithelial Cells and Regulates Allergic Airway Inflammation in an Asthma Murine Model

The mitogen-activated protein kinase (MAPK) signaling pathway is involved in the epithelial-mesenchymal transition (EMT) and asthma; however, the role of mitogen-activated protein kinase kinase kinase 19 (MAP3K19) remains uncertain. Therefore, we investigated the involvement of MAP3K19 in in vitro EMT and ovalbumin (OVA)-induced asthma murine models. The involvement of MAP3K19 in the EMT and the production of cytokines and chemokines were analyzed using a cultured bronchial epithelial cell line, BEAS-2B, in which MAP3K19 was knocked down using small interfering RNA. We also evaluated the involvement of MAP3K19 in the OVA-induced asthma murine model using Map3k19-deficient (MAP3K19-/-) mice. Transforming growth factor beta 1 (TGF-β1) and tumor necrosis factor-like weak inducer of apoptosis (TWEAK) induced the MAP3K19 messenger RNA (mRNA) expression in the BEAS-2B cells. The knockdown of MAP3K19 enhanced the reduction in E-cadherin mRNA and the production of regulated upon activation normal T cell express sequence (RANTES) via stimulation with TWEAK alone or with the combination of TGF-β1 and TWEAK. Furthermore, the expression of MAP3K19 mRNA was upregulated in both the lungs and tracheas of the mice in the OVA-induced asthma murine model. The MAP3K19-/- mice exhibited worsened eosinophilic inflammation and an increased production of RANTES in the airway epithelium compared with the wild-type mice. These findings indicate that MAP3K19 suppressed the TWEAK-stimulated airway epithelial response, including adhesion factor attenuation and RANTES production, and suppressed allergic airway inflammation in an asthma mouse model, suggesting that MAP3K19 regulates allergic airway inflammation in patients with asthma.

Bronchial Asthma, Airway Remodeling and Lung Fibrosis as Successive Steps of One Process

Bronchial asthma is a heterogeneous disease characterized by persistent respiratory system inflammation, airway hyperreactivity, and airflow obstruction. Airway remodeling, defined as changes in airway wall structure such as extensive epithelial damage, airway smooth muscle hypertrophy, collagen deposition, and subepithelial fibrosis, is a key feature of asthma. Lung fibrosis is a common occurrence in the pathogenesis of fatal and long-term asthma, and it is associated with disease severity and resistance to therapy. It can thus be regarded as an irreversible consequence of asthma-induced airway inflammation and remodeling. Asthma heterogeneity presents several diagnostic challenges, particularly in distinguishing between chronic asthma and other pulmonary diseases characterized by disruption of normal lung architecture and functions, such as chronic obstructive pulmonary disease. The search for instruments that can predict the development of irreversible structural changes in the lungs, such as chronic components of airway remodeling and fibrosis, is particularly difficult. To overcome these challenges, significant efforts are being directed toward the discovery and investigation of molecular characteristics and biomarkers capable of distinguishing between different types of asthma as well as between asthma and other pulmonary disorders with similar structural characteristics. The main features of bronchial asthma etiology, pathogenesis, and morphological characteristics as well as asthma-associated airway remodeling and lung fibrosis as successive stages of one process will be discussed in this review. The most common murine models and biomarkers of asthma progression and post-asthmatic fibrosis will also be covered. The molecular mechanisms and key cellular players of the asthmatic process described and systematized in this review are intended to help in the search for new molecular markers and promising therapeutic targets for asthma prediction and therapy.

miR-20b attenuates airway inflammation by regulating TXNIP and NLRP3 inflammasome in ovalbumin-induced asthmatic mice

OBJECTIVES

Asthma is a chronic inflammatory disorder of the airway and is associated with pyroptosis. microRNAs (miRNAs) underlie pathogenic mechanism in asthma. This study is expected to evaluate the role of miR-20b in asthma-induced airway inflammation via regulating thioredoxin-interacting protein (TXNIP) and NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome.

METHODS

The asthmatic mouse model was established via ovalbumin (OVA) induction. Expressions of miR-20b, TXNIP, and NLRP3 in lung tissues were determined. Bronchial hyperresponsiveness was appraised, cells in bronchoalveolar lavage fluid were counted and categorized, and histopathological damage was observed. Levels of inflammatory and pyroptotic cytokines were measured. The binding relationship of miR-20b and TXNIP was testified. Co-location and interaction between TXNIP and NLRP3 were detected. Mice were infected with the lentivirus packaged with pcDNA3.1-TXNIP or pcDNA3.1-NLRP3 for joint experiments to observe the pathological changes of mice.

RESULTS

miR-20b was poorly expressed, while TXNIP and NLRP3 were highly expressed in OVA-induced mice. miR-20b overexpression attenuated airway inflammation and pyroptosis, manifested by alleviation of histopathological damage, declined numbers of total cells and inflammatory cells, lowered bronchial hyperresponsiveness, decreased levels of pro-inflammatory and pyroptotic cytokines, and increased anti-inflammatory cytokines. miR-20b targeted TXNIP and inhibited TXNIP expression, and TXNIP can bind to NLRP3 and upregulated NLRP3 expression. Upregulation of TXNIP or NLRP3 could reverse the protecting role of miR-20b overexpression in OVA-induced mice.

CONCLUSION

miR-20b inhibited TXNIP expression to reduce the binding of TXNIP and NLRP3, thus restricting pyroptosis and airway inflammation of asthmatic mice.

Camellia sinensis (L.) Kuntze Extract Attenuates Ovalbumin-Induced Allergic Asthma by Regulating Airway Inflammation and Mucus Hypersecretion

Asthma is a pulmonary disease induced by the inhalation of aeroallergens and subsequent inappropriate immune responses. Camellia sinensis (L.) Kuntze has been evaluated as an effective antioxidant supplement produced from bioactive compounds, including flavonoids. In this study, we aimed to determine the effects of Camellia sinensis (L.) Kuntze extract (CE) on ovalbumin-induced allergic asthma. The components of CE were analyzed using high-performance liquid chromatography (HPLC) chromatogram patterns, and asthmatic animal models were induced via ovalbumin treatment. The antioxidant and anti-inflammatory effects of CE were evaluated using 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH), 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS), and nitric oxide (NO) assays. Seven compounds were detected in the CE chromatogram. In the ovalbumin-induced mouse model, CE treatment significantly decreased the inflammation index in the lung tissue. CE also significantly decreased eosinophilia and the production of inflammatory cytokines and OVA-specific IgE in animals with asthma. Collectively, our results indicate that CE has anti-inflammatory and antioxidant activities, and that CE treatment suppresses asthmatic progression, including mucin accumulation, inflammation, and OVA-specific IgE production.

Insights on the mechanism of bleomycin to induce lung injury and associated in vivo models: A review

Acute lung injury leads to the development of chronic conditions such as idiopathic pulmonary fibrosis (IPF), chronic obstructive pulmonary disease (COPD), asthma as well as alveolar sarcoma. Various investigations are being performed worldwide to understand the pathophysiology of these diseases, develop novel bioactive compounds and inhibitors to target the ailment. Generally, in vivo models are used to understand the disease outcome and therapeutic suppressing effects for which the animals are chemically or physically induced to mimic the onset of definite disease conditions. Amongst the chemical inducing agents, Bleomycin (BLM) is the most successful inducer. It is reported to target various receptors and activate inflammatory pathways, cellular apoptosis, epithelial mesenchymal transition leading to the release of inflammatory cytokines, and proteases. Mice is one of the most widely used animal model for BLM induced pulmonary associated studies apart from rat, rabbit, sheep, pig, and monkey. Although, there is considerable variation amongst in vivo studies for BLM induction which suggests a detailed study on the same to understand the mechanism of action of BLM at molecular level. Hence, herein we have reviewed various chemical inducers, mechanism of action of BLM in inducing lung injury in vivo, its advantages and disadvantages. Further, we have also discussed the rationale behind various in vivo models and recent development in BLM induction for various animals.

Increased expression of CSF1 in patients with eosinophilic asthma

BACKGROUND

The link between colony-stimulating factor 1 (CSF1) and asthma was reported recently. However, the role and mechanism of CSF1 in asthma remain poorly understood. In this study, we aimed to explore the expression and its potential mechanism of CSF1 in asthma.

METHODS

CSF1 expression in the airway samples from asthmatics and healthy controls were examined, then the correlations between CSF1 and eosinophilic indicators were analyzed. Subsequently, bronchial epithelial cells (BEAS-2B) with CSF1 overexpression and knockdown were constructed to investigate the potential molecular mechanism of CSF1. Finally, the effect of CSF1R inhibitor on STAT1 was investigated.

RESULTS

The expression of CSF1 was significantly increased in patients with asthma compared to healthy controls, especially in patients with severe and eosinophilic asthma. Upregulated CSF1 positively correlated with airway-increased eosinophil inflammation. In vitro, cytokines interleukin 13 (IL-13) and IL-33 can stimulate the upregulation of CSF1 expression. CSF1 overexpression enhanced p-CSF1R/CSF1R and p-STAT1/STAT1 expression, while knockdown CSF1 using anti-CSF1 siRNAs decreased p-CSF1R/CSF1R and p-STAT1/STAT1 expression. Furthermore, the inhibitor of CSF1R significantly decreased p-STAT1/STAT1 expression.

CONCLUSIONS

Sputum CSF1 may be involved in asthmatic airway eosinophil inflammation by interacting with CSF1R and further activating the STAT1 signaling. Interfering this potential pathway could serve as an anti-inflammatory therapy for asthma.

Adenophora Stricta Root Extract Alleviates Airway Inflammation in Mice with Ovalbumin-Induced Allergic Asthma

Adenophora stricta Miq. (Campanulaceae family) is a traditional herb used for relieving cough and phlegm in East Asia. This study explored the effects of A. stricta root extract (AsE) in ovalbumin (OVA)-induced allergic asthma and lipopolysaccharide (LPS)-stimulated macrophages. Administration of 100-400 mg/kg AsE dose-dependently decreased pulmonary congestion and suppressed the reduction of alveolar surface area in mice with OVA-mediated allergic asthma. Histopathological analysis of lung tissue and cytological analysis of bronchioalveolar lavage fluid showed that AsE administration significantly attenuated inflammatory cell infiltration into the lungs. In addition, AsE also alleviated OVA-specific immunoglobulin E, interleukin (IL)-4, and IL-5 production, which are essential for OVA-dependent activation of T helper 2 lymphocytes. In Raw264.7 macrophage cells, AsE significantly blocked nitric oxide, tumor necrosis factor-α, IL-1β, IL-6, and monocyte chemoattractant factor-1 production in response to LPS. Results from an immunoblot assay revealed that AsE inhibited the phosphorylation of c-jun N-terminal kinase, inhibitory-κB kinase α/β, and p65 in LPS-stimulated cells. Furthermore, 2-furoic acid, 5-hydroxymethylfurfural, and vanillic acid 4-β-D-glucopyranoside in AsE were shown to inhibit the production of proinflammatory mediators by LPS. Taken together, the present results suggest that A. stricta root will be a useful herb for relieving allergic asthma through managing airway inflammation.

Mechanistic study of salidroside on ovalbumin-induced asthmatic model mice based on untargeted metabolomics analysis

Salidroside (SAL) is a natural component derived from Rhodiola rosea and is well known for its wide range of biological activities such as its anti-inflammatory and anti-oxidative properties. However, its effects and mechanisms of action related to asthma have not been well explored yet. Recent studies have found that changes in host metabolism are closely related to the progression of asthma. Many natural components can ameliorate asthma by affecting host metabolism. The use of untargeted metabolomics can allow for a better understanding of the metabolic regulatory mechanisms of herbs on asthma. This study aimed to demonstrate the anti-asthmatic effects and metabolic regulatory mechanisms of SAL. In this study, the therapeutic effects of SAL on asthmatic mice were tested at first. Secondly, the effects of SAL on the airway inflammatory reaction, oxidative stress, and airway remodeling were investigated. Finally, untargeted metabolomics analysis was used to explore the influence of SAL on lung metabolites. The results showed that SAL had a significant therapeutic effect on asthmatic model mice. Moreover, SAL treatment lowered interleukin (IL)-4, IL-5, and IL-13 levels but elevated interferon gamma (IFN-γ) and IL-10 levels in bronchoalveolar lavage fluid (BALF). Additionally, it also increased superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities and decreased methane dicarboxylic aldehyde (MDA) levels in the lungs. Besides, SAL-treated mice showed decreased expression of smooth muscle actin (α-SMA), matrix metallopeptidase 2 (MMP2), matrix metallopeptidase 9 (MMP9), and transforming growth factor-beta 1 (TGF-β1) in the lung. Untargeted metabolomics analysis showed 31 metabolites in the lungs that were influenced by SAL. These metabolites were related to pyrimidine metabolism, steroid hormone biosynthesis, and tricarboxylic acid (TCA) cycle. In conclusion, SAL treatment can reduce the inflammatory response, oxidative stress, and airway remodeling in asthmatic model mice. The mechanism of SAL in the treatment of asthma may be related to the regulation of pyrimidine metabolism, steroid hormone biosynthesis, and the TCA cycle. Further studies can be carried out using targeted metabolomics and in vitro models to deeply elucidate the anti-inflammatory and anti-oxidative mechanisms of SAL on asthma based on regulating metabolism.

Molecular Bases of Protein Antigenicity and Determinants of Immunogenicity, Anergy, and Mitogenicity

BACKGROUND

The immune system is able to recognize substances that originate from inside or outside the body and are potentially harmful. Foreign substances that bind to immune system components exhibit antigenicity and are defined as antigens. The antigens exhibiting immunogenicity can induce innate or adaptive immune responses and give rise to humoral or cell-mediated immunity. The antigens exhibiting mitogenicity can cross-link cell membrane receptors on B and T lymphocytes leading to cell proliferation. All antigens vary greatly in physicochemical features such as biochemical nature, structural complexity, molecular size, foreignness, solubility, and so on.

OBJECTIVE

Thus, this review aims to describe the molecular bases of protein-antigenicity and those molecular bases that lead to an immune response, lymphocyte proliferation, or unresponsiveness.

CONCLUSION

The epitopes of an antigen are located in surface areas; they are about 880-3,300 Da in size. They are protein, carbohydrate, or lipid in nature. Soluble antigens are smaller than 1 nm and are endocytosed less efficiently than particulate antigens. The more the structural complexity of an antigen increases, the more the antigenicity increases due to the number and variety of epitopes. The smallest immunogens are about 4,000-10,000 Da in size. The more phylogenetically distant immunogens are from the immunogen-recipient, the more immunogenicity increases. Antigens that are immunogens can trigger an innate or adaptive immune response. The innate response is induced by antigens that are pathogen-associated molecular patterns. Exogenous antigens, T Dependent or T Independent, induce humoral immunogenicity. TD protein-antigens require two epitopes, one sequential and one conformational to induce antibodies, whereas, TI non-protein-antigens require only one conformational epitope to induce low-affinity antibodies. Endogenous protein antigens require only one sequential epitope to induce cell-mediated immunogenicity.

Antiasthmatic Compounds Targeting β2-Adrenergic Receptor from Perilla frutescens Improved Lung Inflammation by Inhibiting the NF-κB Signaling Pathway

Asthma is a highly prevalent and heterogeneous chronic respiratory disease and is often treated with inhaled corticosteroids or in combination with a β₂-adrenergic receptor (β₂-AR) agonist. However, around 5% of asthma remains uncontrolled, and more effective antiasthmatic drugs with known mechanisms are in high demand. Herein, we immobilized β₂-AR on the polystyrene amino microsphere surface in a one-step fashion. The successful immobilization of β₂-AR was verified by scanning electron microscopy and chromatographic analysis. We screened rosmarinic acid (RA) as the bioactive compound targeting β₂-AR in Perilla frutescens (L.) Britton by mass spectroscopy. The binding constant between RA and β₂-AR was determined to be 2.95 × 10⁴ M^-1 by adsorption energy distribution and frontal analysis. The antiasthmatic effect and mechanism of RA were examined on a murine model of allergic asthma induced by ovalbumin (OVA) and aluminum hydroxide. The results showed that RA significantly reduced lung inflammatory cell numbers, the production of Th2 cytokines, and the secretion of total IgE, OVA-specific IgE, and eotaxin. The decreased inflammatory cell infiltration and mucus hypersecretion were associated with the inhibition of the NF-κB signaling pathway. Moreover, the mRNA expression levels of AMCase, CCL11, CCR3, Ym2, and E-selectin in the lung tissues were effectively reduced. It is the first time that RA was proven to target β₂-AR and be effective in counteracting allergic airway inflammation via the NF-κB signaling pathway. Therefore, the immobilized β₂-AR preserves the potential in screening antiasthmatic compounds from herbal medicine, and RA can be developed as an effective agent for the treatment of allergic asthma.

The Interaction of Food Allergy and Diabetes: Food Allergy Effects on Diabetic Mice by Intestinal Barrier Destruction and Glucagon-like Peptide 1 Reduction in Jejunum

The increase in food allergies and diabetes leads to the assumption that they are related. This study aimed to (1) verify the interaction between food allergy and diabetes and (2) explore the potential mechanisms by which food allergy promotes diabetes. Female BALB/c mice were grouped into a control group (CK), an ovalbumin-sensitized group (OVA), a diabetes group (STZ), and a diabetic allergic group (STZ + OVA) (Mice were modeled diabetes with STZ first, then were given OVA to model food allergies), and an allergic diabetic group (OVA + STZ) (Mice were modeled food allergies with OVA first, then were given STZ to model diabetes). The results showed that OVA + STZ mice exhibited a more serious Th2 humoral response, and they were more susceptible to diabetes. Furthermore, when the OVA + STZ mice were in the sensitized state, the intestinal barrier function was severely impaired, and mast cell activation was promoted. Moreover, we found that the effect of food allergy on diabetes is related to the inhibition of GLP-1 secretion and the up-regulation of the PI3K/Akt/mTOR/NF-κB P65 signaling pathway in the jejunum. Overall, our results suggest that food allergies have interactions with diabetes, which sheds new light on the importance of food allergies in diabetes.

Implications of nasal delivery of bromelain on its pharmacokinetics, tissue distribution and pharmacodynamic profile-A preclinical study

Asthma is a polygenic chronic inflammatory respiratory disease devastating the quality of life and state economies. Therefore, utilization of natural products as a therapeutic approach has attained wider consideration for development of novel drugs for asthma management. Bromelain, a mixture of natural bioactive cysteine proteases abundantly found in pineapple stem, has allured attention for its pharmacological activities. However, poor stability in gastric milieu, high dose and immunogenicity associated with prolonged use hinders its oral use. Therefore, need exists to explore alternative route of bromelain administration to achieve its plausible benefits. The present study investigated the preclinical prospects of nasal administration of bromelain on systemic bioavailability, tissue distribution and it's in vivo anti-histaminic, bronchodilator and anti-asthmatic activity in animal models. Pharmacokinetic studies revealed 1.43-fold higher relative bioavailability with faster absorption of bromelain on nasal administration at one-fourth oral dose. The enhanced cellular uptake and localization of bromelain in tissues of lung was observed significantly. Furthermore, faster onset and enhanced antihistaminic, bronchodilator and anti-asthmatic activity on bromelain's nasal administration signified faster absorption and higher in vivo stability of bromelain. Nasal administration significantly achieved decrease in level of oxidative and immunological markers along with restoration of antioxidant enzymes at considerably one-fourth dose administered orally. These findings distinctly manifested that nasal administration could be a substantial and effective route for bromelain delivery with enduring competency in asthma management.

An Amide Alkaloid Isolated from Ephedra sinica Ameliorates OVA-Induced Allergic Asthma by Inhibiting Mast Cell Activation and Dendritic Cell Maturation

Asthma, which is a chronic inflammatory disease of the airways, is usually caused by allergens in which various structures and immune cells are involved. Ephedra sinica, the most commonly used Chinese medicine, has significant clinical effects on asthma, but its components are complex and the mechanism of action has not been fully elucidated. Among its components, we identified an amide alkaloid (EB-A) and investigated its anti-asthmatic activity and the underlying mechanisms. In this study, we replicated an OVA-sensitized/challenged allergic asthma mouse model, and divided the mice into a model (OVA) group, positive drug (Y, 0.5 mg/kg/day) group, and EB-A treatment with low (Low, 10 mg/kg/day) and high dose (High, 20 mg/kg/day) groups. Asthma-related features were analyzed through the airway hyperresponsiveness (AHR), cough and wheeze indexes, allergen-specific IgE, prostaglandin D2 (PDG2), and lung histology in mice. The levels of apoptosis and reactive oxygen species (ROS) in the primary lung cells, cytokines in the serum and broncho-alveolar lavage fluid (BALF), and proteinase-activated receptor-2 (PAR2) pathway activation in the lung tissue were measured to evaluate the inflammatory injury and lung epithelial barrier damage in the mice. Dendritic cell (DC) maturation and mast cell (MC) activation were verified in vitro and in vivo. Furthermore, the effect of a PAR2 activation in lung epithelial cells on the maturation of DCs was evaluated by the co-culture system of (human bronchial epithelial cell lines) 16HBE and bone marrow-derived dendritic cells (BMDCs). The results showed that EB-A inhibited the typical asthmatic phenotypes, as well as lung injury and inflammation, MC activation and degranulation, and DC maturation in the OVA-sensitized/challenged BALB/c mice. In addition, EB-A inhibited the expression of PAR2 in the lung epithelial cells and significantly interfered with the maturation of DCs after inhibiting PAR2. Taken together, our study firstly demonstrated that EB-A could ameliorate OVA-induced allergic asthma by inhibiting MC activation and DC maturation, and the molecular mechanism of EB-A's anti-asthmatic activity might be mediated by inhibiting PAR2. Our data provide a molecular justification for the use of EB-A in the treatment of allergic asthma.

HPLC-DAD analysis of Quercus leucotrichophora extract and appraisal of its antiasthmatic potential via modulation of aquaporins, inflammatory, and oxidative stress biomarkers in Albino mice

Herbal drugs offer an alternative approach for the treatment of diseases like asthma due to low cost and comparatively less adverse effects in contrast to synthetic drugs. Leaves of Quercus leucotrichophora are traditionally used for the treatment of asthma. The study was aimed to assess the anti-asthmatic activity of Quercus leucotrichophora (QL) methanolic (QLME) and aqueous extracts (QLAE) in ovalbumin-(OVA) induced asthma and chemical characterization of QL extract by High Performance Liquid Chromatography-Diode array detector (HPLC-DAD). Animals were inoculated with OVA (i.p) on day 1 and 14 followed by intranasal challenge on 27th and 29th day. Both extracts of QL at 600, 300 and 150 mg/kg and dexamethasone (2 mg/kg) l were administered consecutively from days 15-26 via oral gavage. The QL extracts notably reduced (p < 0.0001-p < 0.05) total and differential leukocyte counts in blood and BALF and serum IgE levels in contrast to disease control. Both extracts and Dex substantially improved activities of superoxide dismutase, catalase, and GSH, while reduced malondialdehyde level in treated mice. Treatment with extracts and Dex caused significant (p < 0.0001-p < 0.05) downregulation of tumor necrosis factor-α, interleukin-4, - 5, - 13, - 6, - 1β, and NF-κB whereas, increased expression of Aquaporin (AQP) 1 and AQP5 in contrast to disease control. It was inferenced from findings that both extract of QL exhibited notable antiasthmatic potential might be due to presence of Daidzein-glucuronic acid, 3-Hydroxyphloretin 6'-hexoside, Catechin, Quercetin, and Kaemferol.

Asthma and Post-Asthmatic Fibrosis: A Search for New Promising Molecular Markers of Transition from Acute Inflammation to Pulmonary Fibrosis

Asthma is a heterogeneous pulmonary disorder, the progression and chronization of which leads to airway remodeling and fibrogenesis. To understand the molecular mechanisms of pulmonary fibrosis development, key genes forming the asthma-specific regulome and involved in lung fibrosis formation were revealed using a comprehensive bioinformatics analysis. The bioinformatics data were validated using a murine model of ovalbumin (OVA)-induced asthma and post-asthmatic fibrosis. The performed analysis revealed a range of well-known pro-fibrotic markers (Cat, Ccl2, Ccl4, Ccr2, Col1a1, Cxcl12, Igf1, Muc5ac/Muc5b, Spp1, Timp1) and a set of novel genes (C3, C3ar1, Col4a1, Col4a2, Cyp2e1, Fn1, Thbs1, Tyrobp) mediating fibrotic changes in lungs already at the stage of acute/subacute asthma-driven inflammation. The validation of genes related to non-allergic bleomycin-induced pulmonary fibrosis on asthmatic/fibrotic lungs allowed us to identify new universal genes (Col4a1 and Col4a2) associated with the development of lung fibrosis regardless of its etiology. The similarities revealed in the expression profiles of nodal fibrotic genes between asthma-driven fibrosis in mice and nascent idiopathic pulmonary fibrosis in humans suggest a tight association of identified genes with the early stages of airway remodeling and can be considered as promising predictors and early markers of pulmonary fibrosis.

Luteolin activates M2 macrophages and suppresses M1 macrophages by upregulation of hsa_circ_0001326 in THP-1 derived macrophages

Asthma is accompanied by inflammatory progression. Macrophages are a major type of cells to response inflammation caused by different type of factors by polarized into specific phenotypes. Luteolin and glycyrrhizic acid exert protect role in asthma; however, their role in THP-1 derived macrophages polarization whether through regulating the expression of hsa_circ_0001326 is still unknown. The effect of luteolin and glycyrrhizic acid on THP-1 derived macrophages polarization were evaluated using qRT-PCR, Western blotting, and ELISA assay. The function of hsa_circ_0001326 on macrophages polarization in luteolin treated THP-1 derived macrophages were assessed after silence of hsa_circ_0001326. And the expression of its’ potential downstream gene, including hsa-miR-136-5p and ubiquitin-specific protease 4 (USP4), were detected using qRT-PCR and Western blot analysis. Furthermore, the potential mechanism of hsa_circ_0001326 were validated using rescue experiment. Results showed that luteolin promoted M2 polarization and inhibited M1 polarization in THP-1 induced macrophages, but glycyrrhizic acid had no these effects. Hsa_circ_0001326 expression was upregulated in luteolin treat THP-1 derived macrophages. Silence of hsa_circ_0001326 reversed the function of luteolin on macrophages polarization. In addition, hsa_circ_0001326 attenuated the inhibition effect of luteolin on hsa-miR-136-5p expression, and the promotion effect on USP4 expression. Furthermore, hsa-miR-136-5p inhibitor reversed the effect of hsa_circ_0001326 on macrophages polarization and the USP4 expression. Taken together, luteolin activates M2 macrophages and suppresses M1 macrophages by upregulation of hsa_circ_0001326. Further mechanism maybe by regulating hsa_circ_0001326 downstream gene expression, including hsa-miR-136-5p and USP4, in THP-1 derived macrophages. These findings provide a new insight for macrophage polarization under stimulation of luteolin.