Asthma, a chronic inflammatory airway disease with a high global prevalence, has a complex pathogenesis, in which airway remodeling plays a key role in the chronicity of the disease. Airway remodeling involves a series of pathophysiological changes, including airway epithelial damage, proliferation of mucous glands and goblet cells, subepithelial fibrosis, proliferation and migration of airway smooth muscle cells, and epithelial-mesenchymal transition. These complex pathological changes significantly increase airway resistance and responsiveness, forming an important pathological basis for refractory asthma. Currently, the regulatory mechanisms of airway remodeling focus on signaling pathways and regulatory targets. The signaling pathways include phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt), nuclear factor-κB(NF-κB), transforming growth factor-β1(TGF-β1)/Smads, and mitogen-activated protein kinase(MAPK). The regulatory targets include microRNAs(miRNAs), competing endogenous RNAs(ceRNAs), long non-coding RNAs(lncRNAs), and circular RNAs(circRNAs). Key proteins involved in these processes include TGF-β1, silencing information regulator 2-related enzyme 1(SIRT1), chitinase 3-like protein 1(YKL-40), and adenosine deaminase-metalloproteinase 33(ADAM33). In recent years, the potential of traditional Chinese medicine in the treatment of asthma has become increasingly evident. Its active ingredients, extracts, and complexes can inhibit airway remodeling in asthma through multiple pathways, demonstrating a variety of effects, including anti-inflammatory actions, inhibition of smooth muscle cell proliferation and migration, regulation of epithelial-mesenchymal transition, attenuation of fibrosis and basement membrane thickening, reduction of mucus secretion, inhibition of vascular remodeling, modulation of immune imbalance, and antioxidative stress. This paper aims to provide an in-depth analysis of the pathogenesis and therapeutic targets of asthma, offering theoretical support and innovative strategies for clinical research and drug development in the treatment of asthma.
Asthma/pathology* ; Humans ; Airway Remodeling/drug effects* ; Drugs, Chinese Herbal/therapeutic use* ; Animals ; Signal Transduction/drug effects* ; Medicine, Chinese Traditional ; Transforming Growth Factor beta1/metabolism*

Objective To investigate whether miR-15b-5p can alleviate airway inflammation in asthma by negatively regulating ubiquitin specific peptidase 9X (USP9X) to down-regulate the expression of phosphatidylinositol 4, 5-diphosphate 3-kinase catalytic subunit α/AKT serine/threonine kinase 1 (PIK3CA/AKT1) pathway. Methods USP9X was predicted to be a direct target of miR-15b-5p by using an online database (miRWalk), and the luciferase reporter gene assay was performed to verify it. Co-immunoprecipitation (CO-IP) was used to verify the direct binding between USP9X and PIK3CA and the role of USP9X and its small molecule inhibitor WP1130 in the deubiquitination of PIK3CA. C57 mice were randomly divided into Control group, OVA group, OVA combined with NC group and miR-15b-5p agomir group, with 10 mice in each group. BEAS-2B cells were induced with interleukin 13 (IL-13) and treated with miR-15b-5p mimic. HE, Masson, PAS, immunohistochemistry, immunofluorescence staining, flow cytometry, Western blot and quantitative real-time PCR(qRT-PCR) were performed. Results It was found that the administration of miR-15b-5p agomir and mimic could reduce peribronchial inflammatory cells and improve airway inflammation, and miR-15b-5p could target negative regulation of USP9X. USP9X could directly bind to PIK3CA and regulate PIK3CA level in a proteasome-dependent manner, and USP9X could deubiquitinate K29-linked PIK3CA protein. Down-regulation of USP9X could increase PIK3CA ubiquitination level. WP1130, a small molecule inhibitor of USP9X, has the same effect as knockdown of USP9X, both of which could increase the ubiquitination level of PIK3CA and reduce the protein level of PIK3CA. Conclusion The miR-15b-5p/USP9X/PIK3CA/AKT1 signaling pathway may provide potential therapeutic targets for asthma.
Animals ; MicroRNAs/metabolism* ; Asthma/pathology* ; Class I Phosphatidylinositol 3-Kinases/genetics* ; Ubiquitin Thiolesterase/metabolism* ; Proto-Oncogene Proteins c-akt/genetics* ; Mice ; Signal Transduction ; Mice, Inbred C57BL ; Humans ; Inflammation/genetics* ; Cell Line ; Female ; Male

OBJECTIVE: To explore the effects and mechanism of Chinese medicine Liujunzi Decoction (LJZD) on regulating microbial flora in mice with asthma flora disorder. METHODS: Thirty BALB/c female mice were divided into control, model, LJZD [3.5 g/(kg•d), by gavage], dexamethasone [DXMS, 0.7 mg/(kg•d), intraperitoneal injection], and Clostridium butyricum [CB, 230 mg/(kg•d), by gavage] groups according to a random number table, 6 mice in each group. The asthma flora disorder mice model was induced with ovalbumin (OVA). Lung and gut lesions were analyzed by hematoxylin-eosin (HE) and periodic acid-Schiff (PAS) stainings. The secretory immunoglobulin A (sIgA) protein expression in lung and gut tissues was detected by Western blot. Flow cytometry was used to detect the relative counts of GATA binding protein 3 (GATA3)/type 2 innate lymphoid cells (ILC2) in lung and gut. The levels of inflammatory factors in lung and gut tissues were detected by enzyme-linked immunosorbent assay (ELISA). Chao1 and Shannon index were used to compare microbial abundance and diversity in alveolar lavage fluid and cecal contents. The similarity or difference in the composition of mice microbial communities was analyzed through cluster analysis. The serum short-chain fatty acids (SCFAs) content was detected by ultra performance liquid chromatograph mass spectrometer (LC-MS)/MS. RESULTS: The asthma flora disorder model mice showed obvious asthma-related symptoms, but LJZD treatment effectively alleviated these symptoms. LJZD restored alveolar wall thickening, airway inflammatory cell infiltration, gut tissue structure destruction, and inflammatory cell infiltration in asthma flora disorder mice. LJZD downregulated the sIgA protein expression in mice (P<0.05). Moreover, LJZD decreased the activation of GATA3/ILC2s in lung and gut tissue (P<0.01), and reduced the levels of interleukin (IL)-5, IL-33, IL-25, IL-9 and IL-13 (P<0.01). LJZD treatment returned the abundance of microbial species and the microbial community structure of alveolar lavage fluid and cecal content in asthma flora disorder mice to the normal state. The SCFAs content and body metabolism were also improved. CONCLUSION LJZD exerted anti-asthmatic effects by improving the microbial balance of lung-gut axis and affecting systemic metabolism, consequently regulating the GATA3/ILC2s axis to impact the lung inflammatory response.
Animals ; Asthma/pathology* ; GATA3 Transcription Factor/metabolism* ; Drugs, Chinese Herbal/therapeutic use* ; Gastrointestinal Microbiome/drug effects* ; Mice, Inbred BALB C ; Female ; Lung/drug effects* ; Homeostasis/drug effects* ; Inflammation/pathology* ; Lymphocytes/drug effects* ; Mice

OBJECTIVES: To explore the mechanism of Pingchuanning Formula (PCN) for inhibiting airway inflammation in rats with asthmatic cold syndrome. METHODS: A total of 105 SD rats were randomized equally into 7 groups, including a control group, an asthmatic cold syndrome model group, 3 PCN treatment groups at high, medium and low doses, a Guilong Kechuanning (GLCKN) treatment group, and a dexamethasone (DEX) treatment group. In all but the control rats, asthma cold syndrome models were established and daily gavage of saline, PCN, GLCKN or DEX was administered 29 days after the start of modeling. The changes in general condition, lung function and lung histopathology of the rats were observed, and inflammatory factors in the alveolar lavage fluid (BALF), oxidative stress, lung tissue ultrastructure, cytokine levels, and expressions of the genes related to the HMGB1/Beclin-1 axis and autophagy were analyzed. RESULTS: The rat models had obvious manifestations of asthmatic cold syndrome with significantly decreased body mass, food intake, and water intake, reduced FEV_0.3, FVC, and FEV_0.3/FVC, obvious inflammatory cell infiltration in the lung tissue, and increased alveolar inflammation score and counts of neutrophils, eosinophils, lymphocytes, macrophages, and leukocytes in the BALF. The rat models also had significantly increased MDA level and decreased SOD level and exhibited obvious ultrastructural changes in the lung tissues, where the expressions of HMGB1, Beclin-1, ATG5, TNF-α, IL-6,IL-1β, and IL-13 and the LC3II/I ratio were increased, while the levels of Bcl-2 and IFN-γ were decreased. PCN treatment significantly improved these pathological changes in the rat models, and its therapeutic effect was better than that of GLKCN and similar to that of DEX. CONCLUSIONS PCN can effectively alleviate airway inflammation in rat models of asthmatic cold syndrome possibly by modulating the HMGB1/Beclin-1 signaling axis to suppress cell autophagy, thereby attenuating airway inflammatory damages.
Animals ; Rats ; Autophagy/drug effects* ; Rats, Sprague-Dawley ; Asthma/pathology* ; Beclin-1 ; HMGB1 Protein/metabolism* ; Drugs, Chinese Herbal/therapeutic use* ; Disease Models, Animal ; Male ; Lung/pathology* ; Inflammation

OBJECTIVETo investigate the effects of ligustrazine (LTZ) on airway inflammation in a mouse model of neutrophilic asthma (NA).

METHODSForty healthy C57BL/6 female mice were randomly divided into 4 groups using a random number table, including the normal control, NA, LTZ and dexamethasone (DXM) groups, with 10 rats in each group. The NA mice model was established by the method of ovalbumin combined with lipopolysaccharide sensitization. At 0.5 h before each challenge, LTZ and DXM groups were intraperitoneally injected with LTZ (80 mg/kg) or DXM (0.5 mg/kg) for 14 d, respectively, while the other two groups were given the equal volume of normal saline. After last challenge for 24 h, the aerosol inhalation of methacholine was performed and the airway reactivity was measured. The bronchoalveolar lavage fluid (BALF) was collected. The Wright-Giemsa staining was used for total white blood cells and differential counts. The levels of cytokines interleukin (IL)-17 and IL-10 were detected by enzyme-linked immunosorbent assay. The pathological change of lung tissue was observed by hematoxylin eosin staining.

RESULTSThe airway responsiveness of the NA group was signifificantly higher than the normal control group (P<0.05), while those in the LTZ and DXM groups were signifificantly lower than the NA group (P<0.05). The neutrophil and eosinophil counts in the LTZ and DXM groups were signifificantly lower than the NA group (P<0.05), and those in the LTZ group were signifificantly lower than the DXM group (P<0.05). There were a large number of peribronchiolar and perivascular inflammatory cells in fifiltration in the NA group. The airway inflflammation in the LTZ and DXM groups were signifificantly alleviated than the NA group. The infifiltration in the LTZ group was signifificantly reduced than the DXM group. Compared with the normal control group, the IL-17 level in BALF was signifificantly increased and the IL-10 level in BALF was signifificantly decreased in the NA group (P<0.05). LTZ and DXM treatment signifificantly decreased IL-17 levels and increased IL-10 levels compared with the NA group (P<0.05), and the changes in the above indices were more signifificant in the LTZ group (P<0.05).

CONCLUSIONLTZ could alleviate the airway inflflammation in the NA mice model through increasing the IL-10 level and decreasing the IL-17 level.

Animals ; Asthma ; blood ; complications ; drug therapy ; pathology ; Bronchoalveolar Lavage Fluid ; cytology ; Disease Models, Animal ; Female ; Interleukin-10 ; metabolism ; Interleukin-17 ; metabolism ; Leukocyte Count ; Lung ; drug effects ; pathology ; Mice, Inbred C57BL ; Neutrophils ; drug effects ; pathology ; Pneumonia ; blood ; complications ; drug therapy ; pathology ; Pyrazines ; pharmacology ; therapeutic use ; Respiratory Hypersensitivity ; blood ; complications ; drug therapy ; pathology

To explore the therapeutic effect of honokiol on particulate matter 2.5 (PM2.5)-induced lung injury in asthmatic mice and the possible mechanisms.
 Methods: A total of 32 BALB/C mice were randomly divided into four groups: a normal saline group, a model group, a PM2.5 group and a honokiol group (n=8 in each group). The asthma mouse model was established by ovalbumin treatment. The mice were treated with physiological saline, ovalbumin, PM2.5 and honokiol, respectively. Lung tissues and serum were collected. The pathological changes of lung tissues were evaluated. The levels of inflammatory cytokines in bronchoalveolar lavage fluid (BALF) and serum were measured and the expressions of Toll like receptor 4 (TLR4), nuclear factor kappa B (NF-κB), retinoid-related orphan receptor gamma-t (RORγt) and forkhead box protein 3 (Foxp3) in lung tissues were detected.
 Results: 1) The lung tissues of mice in the asthma group showed obvious pathological changes and inflammatory state, suggesting that the asthma model was established successfully. PM2.5 could aggravate the pathological condition of inflammatory injury in lung tissues in asthmatic mice. 2) Compared to the PM2.5 group, the pathological symptoms in the lung tissues were alleviated in the honokiol group and the percentage of inflammatory cells in BALF and the levels of inflammatory cytokines in BALF and serum were significantly reduced (all P<0.05). 3) Compared to the PM2.5 group, the expressions of TLR4, NF-κB (p-p65) and RORγt in lung tissues were significantly decreased, while the expression of Foxp3 was increased; the ratio of RORγt/Foxp3 was also decreased in the honokiol group (all P<0.05).
 Conclusion: Honokiol can resist lung injury induced by PM2.5 in asthmatic mice. These effects are through inhibiting TLR4-NF-κB pathway-mediated inflammatory response or regulating the balance of Th17/Treg cells.
Animals ; Asthma ; chemically induced ; complications ; Biphenyl Compounds ; pharmacology ; Bronchoalveolar Lavage Fluid ; chemistry ; Cytokines ; analysis ; Disease Models, Animal ; Drugs, Chinese Herbal ; pharmacology ; Inflammation Mediators ; analysis ; Lignans ; pharmacology ; Lung ; metabolism ; pathology ; Lung Injury ; drug therapy ; etiology ; metabolism ; pathology ; Mice ; Mice, Inbred BALB C ; NF-kappa B ; metabolism ; Ovalbumin ; Particulate Matter ; toxicity ; Random Allocation ; Toll-Like Receptor 4 ; metabolism

OBJECTIVE: To investigate the effect of acupuncture on TGF-β1/Smads signaling pathway in the lung tissue of mice with airway remodeling. METHODS: Thirty specific pathogen-free mice were randomly divided into blank group, model group and acupuncture group (=10). Mouse models of asthma were established in the model group and the acupuncture group, and the mice in the latter group received 7 acupuncture therapies (at bilateral Fei Shu, Da Zhui and Zu Sanli, 20 min each time) every other day, starting on the 10th day after the modeling. At 24 h after the last acupuncture, the mice were subjected to inhalation of 1% OVA for 3 days, and 24 h after the last challenge, the mice were given methacholine chloride (Mch) inhalation at different concentrations for measurement of lung resistance using a noninvasive stroke volume meter. HE staining was used to observe the pathological changes in the lung tissues, and TGF-β1 levels in the the bronchoalveolar lavage fluid (BALF) and serum were detected using ELISA; Western blotting was used to detect the differential protein expressions in the airway smooth muscles between the two groups. The airway smooth muscle cells were isolated from the mice in the acupuncture group and treated with a TGF- β1 inhibitor (LY2157299), and the relative expressions of type-Ⅰ and Smads proteins were detected using Western blotting. RESULTS: The mice in the model showed obvious tracheal fistula with airway pathologies including lumen narrowing, bronchial mucosa thickening, dissociation of the epithelial cells, and thickening of the alveolar septum and airway smooth muscles. These pathological changes were obviously milder in the acupuncture group. The asthmatic mice exhibited significantly increased lung resistance in positive correlation with Mch concentration. Serum TGF-β1 level was significantly elevated in asthmatic mice ( < 0.05); TGF-β1 levels in the serum and BALF were significantly lower in the acupuncture group than in the model group ( < 0.05). In the model group, the expressions of -SMA, TGF-β1 and Smads in the airway smooth muscles were significantly higher than those in the other two groups (both < 0.05). In cultured airway smooth muscle cells, the expressions of type-Ⅰ and Smads were significantly higher in cells treated with LY2157299 than in the control cells (>0.05). CONCLUSIONS Acupuncture can inhibit airway remodeling by inhibiting the expression of airway TGF-β1 and down-regulating the expression of Smads and -SMA to reduce airway inflammatory response. Airway expressions of type-Ⅰ and Smads proteins remain high after inhibiting TGF-β1. Acupuncture may control asthma progression through the TGF-β1/Smads pathway.
Acupuncture Points ; Acupuncture Therapy ; Airway Remodeling ; Airway Resistance ; Animals ; Asthma ; metabolism ; pathology ; therapy ; Bronchi ; pathology ; Disease Progression ; Lung ; metabolism ; physiopathology ; Mice ; Muscle, Smooth ; Random Allocation ; Smad Proteins ; analysis ; metabolism ; Transforming Growth Factor beta1 ; analysis ; metabolism

OBJECTIVEAsthma and chronic obstructive pulmonary disease (COPD) are representative chronic inflammatory airway diseases responsible for a considerable burden of disease. In this article, we reviewed the relationship between neutrophil extracellular traps (NETs) and chronic inflammatory airway diseases.

DATA SOURCESArticles published up to January 1, 2017, were selected from the PubMed, Ovid Medline, Embase databases, with the keywords of "asthma" or "pulmonary disease, chronic obstructive", "neutrophils" and "extracellular traps."

STUDY SELECTIONArticles were obtained and reviewed to analyze the role of NETs in asthma and COPD.

RESULTSNETs are composed of extracellular DNA, histones, and granular proteins, which are released from activated neutrophils. Multiple studies have indicated that there are a large amount of NETs in the airways of asthmatics and COPD patients. NETs can engulf and kill invading pathogens in the host. However, disordered regulation of NET formation has shown to be involved in the development of asthma and COPD. An overabundance of NETs in the airways or lung tissue could cause varying degrees of damage to lung tissues by inducing the death of human epithelial and endothelial cells, and thus resulting in impairing pulmonary function and accelerating the progress of the disease.

CONCLUSIONSExcessive NETs accumulate in the airways of asthmatics and COPD patients. Although NETs play an essential role in the innate immune system against infection, excessive components of NETs can cause lung tissue damage and accelerate disease progression in asthmatics and COPD patients. These findings suggest that administration of NETs could be a novel approach to treat asthma and COPD. Mechanism studies, clinical practice, and strategies to regulate neutrophil activation or directly interrupt NET function in asthmatics and COPD patients are desperately needed.

Animals ; Asthma ; metabolism ; pathology ; Extracellular Traps ; metabolism ; physiology ; Humans ; Neutrophils ; metabolism ; pathology ; Pulmonary Disease, Chronic Obstructive ; metabolism ; pathology

OBJECTIVETo study the expression and significance of the mammalian target of rapamycin (mTOR)/eukaryote initiating factor 4E binding protein 1(4EBP1)/hypoxia inducible factor-1α (HIF-1α)/vascular endothelial growth factor (VEGF) signaling pathway in asthmatic mice.

METHODSForty SPF level 6-8 week-old female Balb/C mice were randomly divided into control, asthma, budesonide and mTOR inhibitor (rapamycin) intervention groups (n=10 each). The asthmatic mouse model was prepared via OVA induction and challenge test. The intervention groups were administered with rapamycin at the dosage of 3 mg/kg by an intraperitoneal injection or budesonide suspension at the dosage of l mg by aerosol inhalation respectively 30 minutes before the OVA challenge. The control and asthma groups were treated with normal saline instead. The concentrations of HIF-1α and VEGF in bronchoalveolar lavage fluid (BALF) were examined using ELISA 24 hours after the last challenge. The pathological changes of lung tissue were observed by hematoxylin-eosin (HE) staining. The p-mTOR and p-4EBP1 from the lung tissues were detected by immunohistochemistry and Western blot. Pearson analysis was used to study the correlation between p-mTOR, p-4EBP1, HIF-1α, and VEGF expression.

RESULTSCompared with the control group, inflammatory cell infiltration and secretions in the trachea increased in the asthma group. The levels of HIF-1α and VEGF in BALF and p-mTOR and p-4EBP1 expression in lung tissues also increased (P<0.01). Compared with the asthma group, inflammatory cell infiltration and secretions in the trachea were reduced in the two intervention groups, and the levels of HIF-1α and VEGF in BALF and p-mTOR and p-4EBP1 expression in lung tissues were also reduced (P<0.01). There were no significant differences in the above changes between the two intervention groups and control group (P>0.05). In the asthma group, there was a pairwise positive correlation between lung p-mTOR and p-4EBP1 expression and HIF-1α and VEGF levels in BALF (P<0.05). However, there were no correlations in the above indexes in the intervention groups and control group.

CONCLUSIONSp-mTOR, p-4EBP1, HIF-1α and VEGF together are involved in the pathogenesis of asthma. Rapamycin treatment can block this signaling pathway, suggesting that this pathway can be used as a novel target for asthma treatment.

Animals ; Asthma ; drug therapy ; metabolism ; Carrier Proteins ; analysis ; physiology ; Female ; Hypoxia-Inducible Factor 1, alpha Subunit ; analysis ; physiology ; Lung ; chemistry ; pathology ; Mice ; Mice, Inbred BALB C ; Phosphoproteins ; analysis ; physiology ; Signal Transduction ; physiology ; TOR Serine-Threonine Kinases ; analysis ; physiology ; Vascular Endothelial Growth Factor A ; analysis ; physiology

BACKGROUND/AIMS: Role of autophagy in neutrophil function and the association of autophagy and autophagy related (ATG) gene polymorphisms with asthma susceptibility were suggested. In this study, we investigated the genetic association of ATG5 and ATG7 polymorphisms with asthma risk, severity and neutrophilic airway inflammation. METHODS: We recruited 408 asthma patients and 201 healthy controls. Sputum neutrophil counts were determined by H&E staining. Serum interleukin 8 (IL-8) levels were measured by enzyme-linked immunosorbent assay (ELISA). Genetic polymorphisms of ATG5 (-769T>C, -335G>A, and 8830C>T) and ATG7 (-100A>G and 25108G>C) were genotyped. The functional activities of ATG5 -769T>C and -335G>A variants were investigated by luciferase reporter assays. RESULTS: No associations of ATG5 and ATG7 polymorphisms with asthma susceptibility and severity were found. ATG5 -769T>C and -335G>A were in complete linkage disequilibrium. In the asthma group, GA/AA genotypes at ATG5 -335G>A were associated with higher neutrophil counts in sputum (p < 0.05); CC/TT genotype at ATG5 8830C>T associated with lower FEV1% predicted value (p < 0.05). DNA fragments containing ATG5 -769T and -335G alleles had higher promoter activities compared to those with -769C and -335A in both human airway epithelial cells (A549, p < 0.01) and human mast cell (HMC-1, p < 0.001). GG and CC genotype at ATG7 -100A>G and 25108G>C were significantly associated with high serum levels of IL-8 (p < 0.05 for both variants). CONCLUSIONS: Genetic polymorphisms of ATG5 and ATG7 could contribute to neutrophilic airway inflammation in the pathogenesis of adult asthma.
Adolescent ; Adult ; Asthma/blood/*genetics/immunology/pathology ; Autophagy/*genetics ; Autophagy-Related Protein 5/*genetics ; Autophagy-Related Protein 7/*genetics ; Case-Control Studies ; Cell Line ; Female ; Gene Frequency ; Genes, Reporter ; Genetic Predisposition to Disease ; Haplotypes ; Heterozygote ; Homozygote ; Humans ; Interleukin-8/blood ; Male ; Middle Aged ; Neutrophil Infiltration/*genetics ; Neutrophils/immunology/metabolism/*pathology ; Phenotype ; *Polymorphism, Single Nucleotide ; Promoter Regions, Genetic ; Risk Factors ; Severity of Illness Index ; Transfection ; Young Adult