Suhuang antitussive capsule at lower doses attenuates airway hyperresponsiveness, inflammation, and remodeling in a murine model of chronic asthma

Medicine Targeting Epithelial-Mesenchymal Transition to Treat Airway Remodeling and Pulmonary Fibrosis Progression

Objective. Dysregulation of epithelial-mesenchymal transition (EMT) in the airway epithelium is associated with airway remodeling and the progression of pulmonary fibrosis. Many treatments have been shown to inhibit airway remodeling and pulmonary fibrosis progression in asthma and chronic obstructive pulmonary disease (COPD) by regulating EMT and have few side effects. This review aimed to describe the development of airway remodeling through the EMT pathway, as well as the potential therapeutic targets in these pathways. Furthermore, this study aimed to review the current research on drugs to treat airway remodeling and their effects on the EMT pathway. Findings. The dysregulation of EMT was associated with airway remodeling in various respiratory diseases. The cytokines released during inflammation may induce EMT and subsequent airway remodeling. Various drugs, including herbal formulations, specific herbal compounds, cytokines, amino acid or protein inhibitors, microRNAs, and vitamins, may suppress airway remodeling by inhibiting EMT-related pathways.

Validity of fractional exhaled nitric oxide and small airway lung function measured by IOS in the diagnosis of cough variant asthma in preschool children with chronic cough

BACKGROUND

To investigate the role of combined impulse oscillometry (IOS) and fractional exhaled nitric oxide (FeNO) in the diagnosis of cough variant asthma (CVA) in preschool children.

METHODS

A total of 197 preschool-aged children with chronic cough were selected from the paediatric outpatient clinic. Allergy histories were collected for all children along with IOS and FeNO. Paediatric respiratory specialists divided the children into a CVA group (n = 90) and a noncough variant asthma (nCVA) group (n = 107) according to the diagnostic criteria for CVA After diagnostic treatment, the correlation between the FeNO and IOS values and the diagnosis in the two groups was analysed, and the area under the curve (AUC) of each index was calculated.

RESULTS

(1) X5 was significantly different between the CVA group and the nCVA group (- 4.22 vs. - 3.64, p < 0.001), as was the FeNO value (29.07 vs. 16.64, p < 0.001). (2) Receiver operating characteristic (ROC) analysis showed that the AUCs of FeNO alone and X5 alone were 0.779 and 0.657, respectively, while the AUC of FeNO (cut-off value of 18 ppb) plus X5 (cut-off value of -4.15 cmH2O/(l/s)) reached 0.809.

CONCLUSIONS

Children with CVA may have small airway dysfunction at an early stage. For preschool children with chronic cough, the combination of FeNO and X5 can better identify those with CVA.

TRIAL REGISTRATION NUMBER

This trial was registered with and approved by the Chinese Clinical Trial Registry, with registration number ChiCTRcRRC-17011738, and was reviewed and approved by the Ethics Committee of Southwest Hospital.

Relief of ovalbumin-induced airway remodeling by the glycyl-l-histidyl-l-lysine-Cu2+ tripeptide complex via activation of SIRT1 in airway epithelial cells

Fixed airflow limitation (FAO), prevalent in patients with severe or difficult-to-treat asthma, is mainly caused by airway remodeling. Airway remodeling is initiated by inflammation and involves subsequent pathological changes. Glycyl-l-histidyl-l-lysine (GHK) is a matrikine with anti-inflammatory and antioxidant effects, naturally existing in human tissue. At present, the GHK level in human plasma and whether it is related to airway remodeling of asthma remain unclear. This study was conducted to determine how GHK is involved in airway remodeling in asthma. Our result showed that the plasma GHK levels of patients with asthma were significantly lower than those of age-matched healthy controls. In asthma patients, plasma GHK levels display a moderate correlation with FEF_25-75%, and patients with FAO had significantly lower GHK levels. Ovalbumin-induced mice of asthma model treated with PBS or GHK-Cu (a form of GHK with higher bioavailability) were used to evaluate the effect of exogenous GHK supplement on airway remodeling. GHK-Cu administration alleviated airway remodeling, as reflected by decreased peribronchial collagen deposition and airway mucus secretion, and suppressed epithelial-mesenchymal transition. The therapeutical effect related to decreased TGF-β1 level. Successively, network pharmacology and the validation data of experiments in vivo and vitro demonstrated that GHK-Cu decreased TGF-β1 level by increasing SIRT1 expression and activating SIRT1 deacetylation in airway epithelial cells, thereby alleviating airway remodeling. Collectively, decreased plasma GHK levels were related to FAO in asthma patients. Through the direct binding and activation of SIRT1, exogenous GHK-Cu administration alleviated airway remodeling in asthmatic mice.

Suhuang Antitussive Capsule Ameliorates Corticosteroid Insensitivity in Cough Variant Asthma Guinea Pigs by Inhibiting p38 MAPK Signal Pathway

Methods

The CVA guinea pig model was successfully established by use of ovalbumin (OVA) sensitization and cigarette smoke (CS) exposure. The guinea pigs were divided into 6 groups: a control group, an OVA model group, an OVA + CS model group, a Suhuang treatment group, a BUD treatment group, and a combination (Suhuang and BUD) treatment group. The effects of the treatment were determined by measuring lung function (RI/Cydn) and cough symptoms (coughs number/cough latency) as outcome criteria. The levels of inflammatory cytokines in bronchoalveolar lavage fluid (BALF) were determined by ELISA. Lung tissues were stained by hematoxylin and eosin (H&E). The expressions of GR/total p38 MAPK/p-p38 MAPK were detected by Western blot. The MKP-1 mRNA levels were detected by RT-PCR.

Results

Combination treatment significantly decreased RI/coughs numbers and increased Cydn/cough latency. Significantly, the results indicated that combination treatment decreased injury to pulmonary tissues. Results also revealed that levels of inflammatory cytokines were reduced in all treatment groups but most markedly in the combination treatment group. Moreover, Suhuang treatment significantly ameliorated corticosteroid insensitivity by improving the expression of glucocorticoid receptors (GR). The expressions of total p38 MAPK and p-p38 MAPK in lung tissue were significantly inhibited in the Suhuang and combination treatment groups. The MKP-1 mRNA levels in Suhuang and combination treatment groups were also increased significantly.

Conclusion

Suhuang was effective for reversing corticosteroid insensitivity by regulating the p38 MAPK signal pathway, and combining BUD and Suhuang treatment showed synergistic interactions in CVA guinea pigs. Our findings showed that this combination therapy might be a promising therapeutic agent for CVA and also clarified its underlying mechanism of action, providing a theoretical basis for clinical combination treatment with Suhuang and BUD in CVA patients.

Suhuang antitussive capsule ameliorates post-infectious cough in mice through AhR-Nrf2 pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Suhuang antitussive capsule (SH capsule), a typical traditional Chinese medicines (TCMs) compound, is widely used for the treatment of post-infectious cough (PIC) in the clinic. Our previous studies have demonstrated that SH capsule possesses significant ameliorative effects on cough variant asthma (CVA), sputum obstruction and airway remodeling.

AIM OF THE STUDY

This study is designed to investigate the ameliorative effects and potential mechanisms of SH capsule on PIC in mice.

MATERIALS AND METHODS

To establish the PIC model, ICR mice were induced by lipopolysaccharide (LPS) (3 mg/kg) once, followed by cigarettes smoke (CS) exposure for 30 min per day for 30 days. Mice were intragastrically (i.g.) administrated with SH capsule at the doses of 3.5, 7, 14 g/kg each day for 2 weeks since the 24th day. The number of coughs, coughs latencies, enzyme-linked immunosorbent assay (ELISA) and histological analysis were used to investigate the effects of SH capsule on PIC mice. Quantitative-polymerase chain reaction (Q-PCR) and western blotting were conducted to evaluate the levels of mRNA and proteins associated with Aryl hydrocarbon receptor (AhR)-NF-E2-related factor 2 (Nrf2) pathway. Superoxide dismutase (SOD), glutathione (GSH) and total antioxidant capacity (T-AOC) assays were performed to evaluate the oxidative stress. A549 cells were used to investigate the ameliorative effects of SH capsule in vitro.

RESULTS

SH capsule effectively diminished the number of coughs and extended coughs latencies in PIC mice. The airway inflammation was alleviated by decreasing the expression levels of inflammatory mediators including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6). Moreover, SH capsule dose-dependently activated AhR-Nrf2 pathway and induced the nuclear translocation in vitro and in vivo. Besides, SH capsule significantly increased the levels of SOD, GSH and T-AOC in mice.

CONCLUSION

Our study demonstrates that SH capsule ameliorates airway inflammation-associated PIC in mice through activating AhR-Nrf2 pathway and consequently alleviating inflammatory responses and oxidative stress.

Jia-Wei-Yu-Ping-Feng-San Attenuates Group 2 Innate Lymphoid Cell-Mediated Airway Inflammation in Allergic Asthma

The incidence of asthma has increased in recent decades. Although corticosteroids and bronchodilators are used in clinical practice, the control of asthma remains a challenge. Allergic asthma is characterized airway inflammation mediated by type 2 immune response. Group 2 innate lymphoid cells (ILC2s) are an important source of type 2 cytokines IL-5 and IL-13, which contribute to the progress of asthma. Jia-Wei-Yu-Ping-Feng-San (JWYPFS), a traditional Chinese medicine, has been widely used to treat asthma in China. In this study we investigated the mechanisms of JWYPFS in the treatment of asthma, especially the effect on ILC2s important in airway inflammation. Female C57BL/6 mice were sensitized and challenged with OVA to establish a model of allergic asthma. Airway hyperresponsiveness was examined by direct airway resistance analysis. Inflammatory cell counts were determined in bronchoalveolar lavage fluid (BALF). Inflammatory cell infiltration and mucus hypersecretion in lung tissue sections was observed by HE and PAS staining, respectively. The numbers and proportions of ILC2s as well as the ILC2s-related transcription factors GATA3, IRF4, and type 2 cytokines were measured in lung tissue samples. Additionally, ILC2s were collected from mouse lung; ILC2s-related cytokines and GATA3 and IRF4 were evaluated after IL-33-induced activation of ILC2s in vitro. Elevated inflammatory cells, mucus secretion, airway hyperresponsiveness and type 2 cytokines in the OVA-treated asthma group indicated that an allergic asthma model had been established. JWYPFS treatment attenuated airway resistance and reduced inflammatory cells including eosinophils, and inhibited mucus production and type 2 cytokines in these asthmatic mice. Moreover, JWYPFS treatment dramatically decreased the numbers and proportions of ILC2s and the mRNA levels of GATA3 and IRF4. In an in vitro experiment JWYPFS significantly suppressed GATA3, IRF4 and type 2 cytokine expression, including IL-5 and IL-13 in IL-33-stimulated ILC2s. JWYPFS alleviates ILC2s-mediated airway inflammation, suggesting that JWYPFS might be an effective agent to treat allergic asthma.

Preservation of mitochondrial homeostasis is responsible for the ameliorative effects of Suhuang antitussive capsule on non-resolving inflammation via inhibition of NF-κB signaling and NLRP3 inflammasome activation

ETHNOPHARMACOLOGICAL RELEVANCE

Suhuang antitussive capsule (Suhuang), one of traditional antitussive Chinese patent medicines, has been used for the treatment of post-infectious cough and cough variant asthma in clinical practice. It has been demonstrated to show numerous biological actions including antitussive and anti-inflammatory effects.

AIM OF THE STUDY

This study aims to investigate the effects of Suhuang on non-resolving inflammation and its underlying molecular mechanism.

MATERIAL AND METHODS

In vitro, mitochondrial membrane potential and ROS were detected by flow cytometry analysis. mtDNA release and mPTP fluorescence were determined by Q-PCR and fluorescence microplate reader analysis. Cytochrome C release and 8-OHdG levels were evaluated by ELISA. Additionally, the effects of Suhuang on Drp1, MMP9, IκBα/NF-κB and NLRP3/ASC/Caspase-1 expression were determined by Q-PCR, gelatin zymography or immunoblot analysis. In vivo, C57/BL6 mice were orally administrated for 2 weeks with Suhuang, then lung injury was induced by LPS. Inflammatory mediators mRNA, histological assessment and NF-κB/Caspase-1/IL-1β levels were evaluated by Q-PCR, H&E staining and immunoblot analysis. Two sepsis models of mice were further used to evaluate its anti-inflammatory effects.

RESULTS

Suhuang restored mitochondrial homeostasis by inhibiting Drp1 activation and mitochondrial fission. Besides, Suhuang reduced mPTP opening, mitochondrial membrane potential collapse, ROS overproduction and mtDNA release. Moreover, Suhuang down-regulated MMP9 expression. As a consequence of preserved mitochondrial homeostasis, Suhuang inhibited NF-κB pathway activation by prevention of NF-κB-p65 phosphorylation and IκBα degradation. Suhuang also limited NLRP3 inflammasome activation by blocking NLRP3-ASC interaction and promoting NLRP3 ubiquitination degradation. Drp1 knockdown in vitro diminished the inhibitory effects of Suhuang on inflammatory responses, indicating the essential role of Drp1 in the Suhuang's activity. Consistently, the therapeutic effects of Suhuang were confirmed in LPS-inhaled mice, which recapitulated the protective actions of Suhuang in mitochondrial homeostasis in vitro. Additionally, two sepsis models of mice confirmed the inhibitory effects of Suhuang on uncontrolled inflammation.

CONCLUSIONS

Altogether, our work reveals that Suhuang inhibits non-resolving inflammation through inhibition of NF-κB signaling and NLRP3 inflammasome activation by preserving mitochondrial homeostasis, providing new pharmacological data for the clinical use of Suhuang. Our study also suggests mitochondrial homeostasis as a potential intrinsic regulatory strategy for treating inflammatory diseases.

ORMDL3 Promotes Angiogenesis in Chronic Asthma Through the ERK1/2/VEGF/MMP-9 Pathway

AIM

Angiogenesis plays a vital role in airway remodeling in chronic asthma. ORMDL3 has been identified to be closely associated with the development of asthma remodeling. This study was to investigate the mechanism of ORMDL3 in angiogenesis of chronic asthma.

METHODS

BALB/c mice were divided into three groups, including an asthmatic group (group A), a budesonide-treated group (group B), and a normal control group (group C). Hematoxylin and eosin and Masson staining were used to evaluate the pathological changes. Angiogenesis in lung tissue was examined by CD31 staining. The changes of ORMDL3, ERK1/2, and angiogenesis-associated MMP-9 and Vascular endothelial growth factor (VEGF) expression were examined. Furthermore, ORMDL3, MMP-9, and VEGF mRNA and protein levels were examined after transfection in BEAS-2B cells with the ORMDL3-overexpressed lentiviral vector.

RESULTS

Compared with the control group, asthmatic mice indicated more severe airway angiogenesis with increased ORMDL3, ERK1/2, MMP-9, and VEGF expression. Budesonide alleviated airway angiogenesis, and CD31 expression was positive with the levels of ORMDL3, MMP-9, and VEGF (P < 0.01). After successful transfection in BEAS-2B cells with the ORMDL3-overexpressing lentiviral vector, VEGF, and MMP-9 expression were activated in vitro (P < 0.01).

CONCLUSION

In conclusion, our study provides novel evidence that ORMDL3 promotes angiogenesis through upregulating VEGF and MMP-9 in chronic asthma.

Panax notoginseng saponin R1 modulates TNF-α/NF-κB signaling and attenuates allergic airway inflammation in asthma

BACKGROUD

Panax notoginseng saponin R1 (PNS-R1) is one of the most important chemical monomers derived from the panax notoginseng, and our previous study found that PNS-R1 reduced glucocorticoid-induced apoptosis in asthmatic airway epithelial cells. Thus, in this study, we explored the effects of the PNS-R1 on inflammation of allergic asthma.

METHODS

The asthmatic mice were administered 15 mg/kg PNS-R1 by intraperitoneal injection three days before sensitized to OVA. The effects of PNS-R1 on asthmatic mice were detected by airway hyperresponsiveness, inflammation, mucus hypersecretion and inflammatory cytokines such as interleukin (IL)-13, IL-4, IL-5, IL-8 and tumor necrosis factor (TNF)-α were studied. We also treated human bronchial epithelial cells (16HBE) with house dust mites (HDM) and then detected the secretion of cellular inflammatory factors (IL-13 and TNF-α). Western blot and immunofluorescence were used to examine the effect of PNS-R1 on TNF-α/NF-κB pathway. TNF-α/NF-κB/IKK signal pathway activator was used in PNS-R1-treated asthmatic mice.

RESULTS

PNS-R1 significantly reduced the airway inflammatory, mucus secretion and hyperresponsiveness in asthma model. It also reduced the levels of IL-13, IL-4, IL-5 and IL-8 in bronchoalveolar lavage fluid (BALF) and IgE and OVA-specific IgE in serum for asthma mice. PNS-R1 reduced IL-13 and TNF-α secretion in HDM-treated 16HBE cells. In addition, PNS-R1 suppressed TNF-α/NF-κB pathway in both asthmatic mice and 16HBE. Activation of NF-kB pathway reversed the therapeutic effect of PNS-R1 on asthmatic mice.

CONCLUSION

The results indicated that PNS-R1 effectively suppresses allergic airway inflammation of asthma partly through TNF-α/NF-κB pathway. PNS-R1 may play a potential role in allergic asthma treatment in the future.

Adelmidrol: A New Promising Antioxidant and Anti-Inflammatory Therapeutic Tool in Pulmonary Fibrosis

BACKGROUND

Chronic pulmonary diseases are characterized by airway remodeling due to complex multicellular responses and the production of free oxygen radicals. They lead to a progressive decline of pulmonary functions. Adelmidrol is an analogue of palmitoylethanolamide (PEA), which is a well-known anti-inflammatory and anti-oxidant compound. In this study, we investigated the efficacy of adelmidrol (10 mg/Kg) for bleomycin-induced pulmonary fibrosis in mice.

METHODS

Bleomycin intratracheal administration was performed on the first day and for the following twenty-one days, mice were treated with adelmidrol (10 mg/Kg).

RESULTS

The survival rate and body weight gain were recorded daily. At the end of the experiment, adelmidrol-administered animals showed reduced airway infiltration by inflammatory cells, Myeloperoxidase (MPO) activity, and pro-inflammatory cytokine overexpression (IL,6 IL-1β, TNF-α, and TGF-1β). Moreover, adelmidrol treatment was able to manage the significant incapacity of antioxidants and elevation of the oxidant burden, as shown by the MDA, SOD, and GSH levels and decreased nitric oxide production. It was also able to significantly modulate the JAK2/STAT3 and IκBα/NF-kB pathway. Histologic examination of the lung tissues showed reduced sample injury, mast cell degranulation, chymase activity, and collagen deposition.

CONCLUSIONS

In sum, our results propose adelmidrol as a therapeutic approach in the treatment of pulmonary fibrosis.

Soufeng Yuchuan decoction mitigates the ovalbumin-induced lung damage in a rat model of asthma

Airway remodeling is a key feature of asthma. Extracellular matrix synthesis and vascular remodeling respectively regulated by transforming growth factor (TGF-β1) and vascular endothelial growth factor (VEGF), are important for the airway remodeling. This study aimed to investigate the effect of Soufeng Yuchuan (SFYC) decoction, a Traditional Chinese Medicine, on airway remodeling and expression of VEGF and TGF-β1 in asthma model rats. A rat model of asthma was induced by ovalbumin (OVA) treatment. The results showed that SFYC decoction improved general conditions and reduced the damage in lung tissues in asthma model rats. Furthermore, SFYC decoction significantly reduced the OVA-induced levels of VEGF and TGF-β1 in sera and in bronchoalveolar lavage fluid. Moreover, SFYC decoction decreased the OVA-induced VEGF mRNA and protein levels in lung tissues in asthma model rats. Interestingly, SFYC with high dose was more potent in reducing TGF-β1 level in rat sera and BALF than dexamethasone (positive control). In summary, SFYC decoction effectively mitigates lung damage in OVA-induced asthma model rats, which was associated with inhibition of VEGF and TGF-β1.

Suhuang Antitussive Capsules-Ameliorative Effects on LPS-Induced Sputum Obstruction in Mice Through Promoting HGF Secretion

Sputum obstruction is one of common cough complications, which is tightly associated with airway inflammation. Suhuang antitussive capsule (SH Capsule), a classic traditional Chinese medicine prescription, has been used for the treatment of post-cold cough and cough variant asthma in the long clinical application. This study aims to investigate the effects and underlying mechanisms of SH Capsule on LPS-induced sputum obstruction in mice. The results showed that SH Capsule effectively promoted the tracheal phenol red output and mucociliary clearance. SH Capsule also alleviated airway inflammation-mediated mucin 5AC (MUC5AC) level through EGFR-ERK signaling. A further in vivo analysis showed that HGF inhibitor SU11274 abrogated the effects of SH Capsule on MUC5AC, well demonstrating that HGF was required for the beneficial effects of SH Capsule on expectoration in vivo. Moreover, SH Capsule promoted HGF secretion in a colon-dependent manner, which reached lung tissues via blood circulation. Collectively, this study provided new pharmacological data for clinical use of SH Capsule, and proposed a novel mechanism by which SH Capsule was pharmacologically promising for treating sputum obstruction.

Emodin Alleviates the Airway Inflammation of Cough Variant Asthma in Mice by Regulating the Notch Pathway

Background

This study investigated the effects and underlying mechanisms of emodin on cough variant asthma (CVA) in mice.

Material/Methods

The bronchial asthma mouse model was successfully established by use of ovalbumin (OVA) sensitization and challenge. The BALB/c mice were divided into 6 groups: a control group, an OVA model without or with emodin (15, 30, 60 mg/kg) group, and a dexamethasone (0.5 mg/g) group. The effect of the treatment was determined by measuring airway responsiveness. The levels of immunoglobulin molecules, as well as inflammatory cytokines in bronchoalveolar lavage fluid (BALF) and serum, were determined by ELISA. The lung tissues were stained by hematoxylin-eosin (HE). The expressions of Notch receptors (Notch 1–3) and Delta-like (DLL) 4 in the lung tissues were detected by RT-PCR and Western blot analysis.

Results

Compared with the model group, emodin treatment significantly increased the levels of immunoglobulin E (IgE) and IgG1/IgG2a in BALF and serum (p<0.05). HE results indicated that emodin inhibited the infiltration of inflammatory cells and that emodin reduced the levels of inflammatory cytokines, interleukin (IL)-5, IL-17, and interferon (IFN)-γ in BALF and serum (p<0.05). Furthermore, the expressions of Notch 1, 2, 3, and DLL4 in lung tissue were inhibited by emodin treatment.

Conclusions

The results demonstrated that emodin alleviated inflammation in CVA mice, which might be associated with suppression of the Notch pathway. Emodin might be a promising therapeutic agent for allergic asthma.

Suhuang antitussive capsule inhibits NLRP3 inflammasome activation and ameliorates pulmonary dysfunction via suppression of endoplasmic reticulum stress in cough variant asthma

Pulmonary dysfunction is tightly associated with cough variant asthma (CVA), a respiratory damage disease. Suhuang antitussive capsule (Suhuang), one of traditional Chinese patent medicines, plays a crucial role in the treatment and complication of CVA in the long clinical application. In this study, we aimed to investigate the protective effects and underlying antitussive mechanisms of Suhuang on pulmonary function in ovalbumin (OVA)-induced CVA rats. Administration (i.g.) of Suhuang significantly alleviated pulmonary damage and dysfunction. Suhuang improved ER stress and PKCε translocation via regulation of Ca²⁺ trafficking. Suhuang also inhibited NLRP3 inflammasome activation, as evidenced by disrupting the assembly of NLRP3 inflammasome and reducing the expression of cleaved caspase-1, and decreased IL-1β secretion. Besides, it's identified that TXNIP induction and RIP1-RIP3-Drp1 pathway were required for the inhibitory routes of Suhuang from ER stress to NLRP3 inflammasome activation. Consistent with the in vivo findings, Suhuang also attenuated ER stress/NLRP3 inflammasome activation, and thereby restored pulmonary homeostasis in vitro. Meantime, these functions were diminished by blocking ER stress, indicating that ER stress is essential for the effects of Suhuang on pulmonary function. A further in vivo analysis showed that Suhuang-driven pharmacological inactivation of NLRP3 inflammasome and amelioration of pulmonary dysfunction were reversed by an ER stress inducer tunicamycin, well confirming the beneficial effects of Suhuang on pulmonary function by regulation of ER stress. Collectively, these results indicated that Suhuang contributed to impairing NLRP3 inflammasome activation via inhibition of ER stress, which was responsible for the protection of pulmonary homeostasis. These findings may provide a pharmacological groundwork and important new experimental data regarding the clinical treatment of Suhuang in CVA patients.

Fractional Exhaled Nitric Oxide (FeNO) Combined with Pulmonary Function Parameters Shows Increased Sensitivity and Specificity for the Diagnosis of Cough Variant Asthma in Children

Background

Cough variant asthma in children presents with a dry nonproductive cough. This study aimed to investigate the diagnostic value of fractional exhaled nitric oxide (FeNO) combined with small airway functional parameters in cough variant asthma.

Material/Methods

Children with asthma (n=136) were divided into a cough variant asthma (CVA) group (n=57; mean age, 8.03±2.1 years) and a non-cough variant asthma (nCVA) group (n=79; mean age, 8.61±1.7 years). In both groups, FeNO and other pulmonary function parameters were measured including forced expiratory volume in one second (FEV1), forced vital capacity (FVC), peak expiratory flow (PEF), maximum mid-expiratory flow (MMEF), forced expiratory flow (FEF), and maximum expiratory flow at 25%, 50%, and 75% expired volume (MEF25, MEF50, and MEF75). Receiver-operating characteristic (ROC) curve analysis compared the sensitivity and specificity between the diagnostic parameters.

Results

The FeNO values were significantly increased in the CVA group compared with the nCVA group (Z=6.890, p<0.001). The MMEF, MEF25, MEF50, and MEF75 values were significantly lower in the CVA group compared with the nCVA group (p=0.000, p=0.014, p=0.000, and p=0.000, respectively). The FeNO values were negatively correlated with MEF25, MEF50, and MMEF (r=−0.334, r=−0.257 and r=−0.276, respectively). FeNO was significantly more efficient diagnosing cough variant asthma comparing with pulmonary parameters (p<0.05), and was most sensitive and specific when combined with MMEF/MEF50 compared with single diagnostic parameters (p<0.05).

Conclusions

FeNO combined with pulmonary function parameters of MMEF/MEF50 showed increased sensitivity and specificity for the diagnosis of cough variant asthma.

The Anti-Inflammatory Effects of Fermented Herbal Roots of Asparagus cochinchinensis in an Ovalbumin-Induced Asthma Model

Introduction: Roots of Asparagus cochinchinensis, which have pharmacologically active ingredients, have received great attention because they show good therapeutic effects for various inflammatory diseases without specific toxicity. This study investigated the anti-asthmatic effects of a butanol extract of Asparagus cochinchinensis roots that had been fermented with Weissella cibaria (BAW) and its possible underlying cholinergic regulation. Methods: Alterations of the anti-asthmatic markers and the molecular response factors were measured in an ovalbumin (OVA)-induced asthma model after treatment with BAW. Results: Treatment with BAW decreased the intracellular reactive oxygen species (ROS) production in lipopolysaccharides (LPS) activated RAW264.7 cells. The results of the animal experiments revealed lower infiltration of inflammatory cells and bronchial thickness, and a significant reduction in the number of macrophages and eosinophils, concentration of OVA-specific IgE, and expression of Th2 cytokines in the OVA + BAW treated group. In addition, a significant recovery of goblet cell hyperplasia, MMP-9 expression, and the VEGF signaling pathway was observed upon airway remodeling in the OVA + BAW treated group. Furthermore, these responses of BAW were linked to recovery of acetylcholine esterase (AChE) activity and muscarinic acetylcholine receptor (mAChR) M3 downstream signaling pathway in epithelial cells, smooth muscle cells, and afferent sensory nerves of OVA + BAW-treated mice. Conclusion: Overall, these findings are the first to provide evidence that the therapeutic effects of BAW can prevent airway inflammation and remodeling through the recovery of cholinergic regulation in structural cells and inflammatory cells of the chronic asthma model.

Functional Cooperation between KCa3.1 and TRPV4 Channels in Bronchial Smooth Muscle Cell Proliferation Associated with Chronic Asthma

Airway smooth muscle cells (SMC) proliferation contributes to the airways remodeling and irreversible airway obstruction during severe asthma, but the mechanisms of airway SMC proliferation are poorly understood. Intracellular Ca²⁺ levels play an important role in regulating cell proliferation. We have previously reported KCa3.1 channels regulated human bronchial smooth muscle (HBSM) cells proliferation via the Ca²⁺ influx as a consequence of membrane hyperpolarization. However, the role of potassium channels KCa3.1 in airway remodeling as well as the mechanism for extracellular Ca²⁺ influx induced by the activation of KCa3.1 remains unknown. Here we demonstrated that KCa3.1 channels deficiency attenuated airway remodeling, airway inflammation, and airway hyperresponsiveness (AHR) in a mouse model of chronic asthma. The gene expressions of repressor element 1-silencing transcription factor (REST) and c-Jun, two transcriptional regulators of KCa3.1 channels, were correlated negatively or positively with KCa3.1 channels expressions both in vivo and in vitro using real-time PCR and Western blot analyses. RNAi-mediated knockdown or pharmacological blockade of KCa3.1 and TRPV4 significantly attenuated HBSM cells proliferation. Using confocal imaging and custom data analysis software, blockade of TRPV4 decreased the Ca²⁺ influx induced by 1-EBIO-mediated KCa3.1 activation. Double-labeled staining showed that KCa3.1 and TRPV4 channels colocalized in HBSM cells. These results demonstrate that KCa3.1 channels regulate the proliferation phenotype of HBSM cells via TRPV4 channels in the process of chronic asthma, making it a potential therapeutic target to treat chronic asthma.

Herbal Medicines for Asthmatic Inflammation: From Basic Researches to Clinical Applications

Asthma is one of the most common chronic inflammatory disorders, associated with reversible airflow obstruction, airway hyperresponsiveness, and airway remodeling. This disease has a significant impact on individuals, their families, and society. Standardized therapeutics such as inhaled corticosteroid in combination with long acting β2 agonist have been applied for asthma control; however, complementary and alternative medicines, especially herbal medicines, are still widely used all over the world. A growing body of literature suggests that various herbals or related products might be effective in inhibiting asthmatic inflammation. In this review, we summarize recent advances about the mechanistic studies of herbal medicines on allergic airway inflammation in animal models and their potential application into clinic for asthma control.

Matrine suppresses airway inflammation by downregulating SOCS3 expression via inhibition of NF-κB signaling in airway epithelial cells and asthmatic mice

Matrine has been demonstrated to attenuate allergic airway inflammation. Elevated suppressor of cytokine signaling 3 (SOCS3) was correlated with the severity of asthma. The aim of this study was to investigate the effect of matrine on SOCS3 expression in airway inflammation. In this study, we found that matrine significantly inhibited OVA-induced AHR, inflammatory cell infiltration, goblet cell differentiation, and mucous production in a dose-dependent manner in mice. Matrine also abrogated the level of interleukin (IL)-4 and IL-13, but enhanced interferon (IFN)-γ expression, both in BALF and in lung homogenates. Furthermore, matrine impeded TNF-α-induced the expression of IL-6 and adhesion molecules in airway epithelial cells (BEAS-2B and MLE-12). Additionally, we found that matrine inhibited SOCS3 expression, both in asthmatic mice and TNF-α-stimulated epithelial cells via suppression of the NF-κB signaling pathway by using pcDNA3.1-SOCS3 plasmid, SOCS3 siRNA, or nuclear factor kappa-B (NF-κB) inhibitor PDTC.

CONCLUSIONS

Matrine suppresses airway inflammation by downregulating SOCS3 expression via inhibition of NF-κB signaling in airway epithelial cells and asthmatic mice.