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

OBJECTIVETo investigate the changes in the mRNA and protein expression of high-mobility group box 1 (HMGB1), Toll-like receptor 4 (TLR4), and nuclear factor-kappa B (NF-κB) in lung tissues of asthmatic mice and the interventional effect of vitamin D.

METHODSA total of 48 BALB/c mice were randomly divided into control group, asthma group, and 1,25-(OH)Dintervention group, with 16 mice in each group. An animal model of asthma was established, and lung tissue samples were taken in each group at weeks 1 and 2 of ovalbumin challenging. Conventional hematoxylin-eosin staining was used to measure airway wall thickness. Immunohistochemical staining was used to observe the expression of HMGB1, TLR4, and NF-κB in lung tissues. Quantitative real-time PCR and Western blot were used to investigate the changes in the mRNA and protein expression of HMGB1, TLR4, and NF-κB.

RESULTSAt weeks 1 and 2 of ovalbumin challenging, compared with the control group, the asthma group had a significant increase in airway wall thickness and the intervention group had a significant reduction compared with the asthma group (P<0.05). The asthma group had significantly higher mRNA expression of HMGB1, TLR4, and NF-κB in lung tissues than the control group, and the intervention group had significantly lower mRNA expression of TLR4 and NF-κB than the asthma group (P<0.05). At week 1 of ovalbumin challenging, there was no significant difference in the mRNA expression of HMGB1 between the intervention group and the asthma group (P>0.05). At week 2, the intervention group had a significant reduction in the mRNA expression of HMGB1 compared with the asthma group (P<0.05). At weeks 1 and 2 of ovalbumin challenging, the asthma group had significantly higher protein expression of HMGB1, TLR4, and NF-κB in lung tissues than the control group, and the intervention group had significantly lower expression than the asthma group (P<0.05). Airway wall thickness was positively correlated with the mRNA expression of HMGB1, TLR4, and NF-κB in lung tissues (r=0.804, 0.895, and 0.834; P<0.05).

CONCLUSIONSThe HMGB1/TLR4/NF-κB signaling pathway plays an important role in the pathogenesis of asthma, and an appropriate amount of 1,25-(OH)Dhas a regulatory effect on this pathway and may prevent the progression of asthma. Therefore, 1,25-(OH)Dis expected to become a new choice for the treatment of asthma.

Animals ; Asthma ; drug therapy ; etiology ; pathology ; Calcitriol ; therapeutic use ; Female ; HMGB1 Protein ; analysis ; physiology ; Lung ; pathology ; Mice ; Mice, Inbred BALB C ; NF-kappa B ; analysis ; physiology ; Signal Transduction ; physiology ; Toll-Like Receptor 4 ; analysis ; physiology

OBJECTIVETo study the effects of the change in transient receptor potential vanilloid 1 (TRPV1) channel activity on the degree of airway inflammation in asthmatic mice.

METHODSBALB/c mice were randomly divided into control, asthma, capsaicin (TRPV1 agonist), capsazepine (TRPV1 antagonist), and dexamethasone groups. The asthmatic mouse model was established by intraperitoneal injection of mixed ovalbumin-aluminium hydroxide solution and ultrasonic atomization with OVA for sensitization and challenge. The capsaicin, capsazepine, and dexamethasone groups were given intraperitoneal injection of capsaicin (30 μg/kg), capsazepine (10 μmol/kg), and dexamethasone (2 mg/kg) respectively, at 30 minutes before challenge. Hematoxylin and eosin staining was used to observe the degree of pulmonary inflammation. ELISA was used to measure the content of interleukin-8 (IL-8) and interleukin-13 (IL-13) in bronchoalveolar lavage fluid (BALF). Real-Time PCR was used to measure the relative content of TRPV1 mRNA in lung tissue.

RESULTSCompared with the asthma group, the capsazepine and dexamethasone groups showed reduced pulmonary inflammation, while the capsaicin group showed aggravated pulmonary inflammation. Compared with the control group, the asthma and capsaicin groups showed increases in the content of IL-13 and IL-8 in BALF and the mRNA expression of TRPV1 in lung tissue (P<0.05). Compared with the asthma group, the capsazepine and dexamethasone groups showed reductions in the content of IL-13 and IL-8 in BALF and the mRNA expression of TRPV1 in lung tissue (P<0.05). The capsaicin group showed increases in the content of IL-13 and IL-8 in BALF (P<0.05).

CONCLUSIONSTRPV1 channel agonist and antagonist can influence the degree of airway inflammation in asthmatic mice. Dexamethasone may reduce airway inflammation through regulating TRPV1 level.

Animals ; Asthma ; etiology ; Female ; Interleukin-13 ; analysis ; Interleukin-8 ; analysis ; Lung ; pathology ; Mice ; Mice, Inbred BALB C ; RNA, Messenger ; analysis ; TRPV Cation Channels ; genetics ; physiology

OBJECTIVETo investigate the pathogenic mechanisms of airway inflammation and recurrent wheezing induced by recurrent respiratory virus infection after respiratory syncytial virus (RSV) infection.

METHODSSixty-four female BALB/c mice (aged 6-8 weeks) were randomly divided into four groups: control, RSV, Poly(I:C), and RSV+Poly(I:C) (n=16 each). The bronchoalveolar lavage fluid (BALF) was collected on the 3rd day after Poly(I:C) administration, and the total cell number and differential counts in BALF were determined. Hematoxylin-eosin staining was used to observe pulmonary pathological changes. The airway responsiveness was detected. ELISA was used to measure the levels of interferon-γ (IFN-γ), interleukin-4 (IL-4), interleukin-13 (IL-13), matrix metallopeptidase-9 (MMP-9), and tissue inhibitor of metalloproteinase-1 (TIMP-1) in BALF.

RESULTSCompared with the other three groups, the RSV+Poly(I:C) group had significant increases in the total number of inflammatory infiltrating cells in the airway, airway responsiveness, and MMP-9 level in BALF (P<0.05). The RSV+Poly(I:C) group showed more severe pulmonary tissue injuries compared with the control and RSV groups (P<0.01). Compared with the RSV group, the RSV+Poly(I:C) group showed significant reductions in the levels of IL-4 and TIMP-1 in BALF (P<0.01).

CONCLUSIONSViral re-infection in the late stage of RSV infection may cause an imbalance of MMP-9/TIMP-1 expression and thus contribute to aggravated airway inflammation.

Animals ; Asthma ; etiology ; Bronchoalveolar Lavage Fluid ; chemistry ; Female ; Lung ; pathology ; Matrix Metalloproteinase 9 ; analysis ; Mice ; Mice, Inbred BALB C ; Poly I-C ; pharmacology ; Respiratory Syncytial Virus Infections ; complications ; Tissue Inhibitor of Metalloproteinase-1 ; analysis

BACKGROUNDIt has already been recognized that psychosocial stress evokes asthma exacerbation; however, the mechanism of how stress gets inside the body is not clear. This study aimed to observe the impact of psychosocial stress on airway inflammation and its mechanism in the ovalbumin-induced asthmatic mice combined with social disruption stress.

METHODSThirty-six male BALB/c mice were randomly divided into: control group, asthma group (ovalbumin-induced), asthma plus social disruption stress group (SDR), and SDR group. The open field video tracking system was used to assess animal behaviors. The invasive pulmonary resistance (RL) and dynamic lung compliance (cdyn) test system from Buxco was applied to detect pulmonary function. The enzyme-linked immunosorbent assay (ELISA) was utilized to determine OVA-IgE, T-helper type 2 (Th2) cytokines (IL-4, IL-5, IL-13) and corticosterone in mouse serum, the Th2 cytokines (IL-4, IL-5, IL-13, IL-6, TNF-α) in bronchoalveolar lavage fluid (BALF), and IL-6 and TNF-α levels in the supernatant of splenocytes cultured in vitro. Hematoxylin-eosin (H&E) staining was used to assess airway inflammation in lung histology. The cell count kit-8 assay (CCK-8) was applied to evaluate the inhibitory effect of corticosterone on splenocyte proliferation induced by lipopolysaccharide (LPS). Real time-PCR and Western blotting were utilized to determine glucocorticoid receptor (GR) mRNA and GR protein expression in lungs.

RESULTSThe open field test showed that combined allergen exposure and repeated stress significantly shortened the time the mice spent in the center of the open field (P < 0.01), increased ambulatory activity (P < 0.01) and the count of fecal boli (P < 0.01), but deceased vertical activity (P < 0.01). Results from pulmonary function demonstrated that airway hyperresponsiveness (AHR) was enhanced by psychosocial stress compared with allergy exposure alone. The ELISA results showed that cytokines in serum and BALF were significantly increased (P < 0.05). Moreover, the lung histology showed that infiltrated inflammatory cells were significantly increased in the asthma-SDR group compared with the asthma group (P < 0.05). Interestingly, serum corticosterone was remarkably raised by psychosocial stress (P < 0.05). In addition, the inhibitory effect of corticosterone on IL-6 and TNF-α in LPS-stimulated splenocyte cultures in vitro was diminished in the asthma-SDR group compared to the asthma group. The CCK-8 test revealed that the inhibition effect of corticosterone on splenocyte proliferation induced by LPS was significantly impaired in the SDR and asthma-SDR groups, while no significant effect was observed in the control and asthma groups. Furthermore, expression of GR mRNA and GR protein were significantly reduced in the lung tissues of the asthma-SDR group (P < 0.05).

CONCLUSIONSSocial disruption stress can promote anxiety behavior, activate the hypothalamic-pituitary-adrenal (HPA) axis, increase AHR and inflammation, and also impair glucocorticoid sensitivity and its function in a murine model of asthma. The down-regulation of GR expression induced by social disruption stress is in part associated with glucocorticoid insensitivity, which leads to asthma exacerbation.

Animals ; Anxiety ; etiology ; Asthma ; etiology ; Bronchial Hyperreactivity ; etiology ; Corticosterone ; blood ; Cytokines ; biosynthesis ; Disease Models, Animal ; Lung ; pathology ; Male ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; Receptors, Glucocorticoid ; analysis ; physiology ; Stress, Psychological ; complications

Primary tracheal tumours are rare and less frequently observed than bronchial tumours. Primary neurogenic tumours of the trachea as schwannomas or neurilemmomas are extremely uncommon. We report a tracheal schwannoma in a female patient who presented with breathlessness and wheeze, and she was being treated for asthma. Flexible bronchoscopy revealed a large pedunculated tracheal mass and biopsy confirmed schwannoma. She was treated with laser ablation with partial reduction of the tumour. Subsequently, she was lost to follow-up, although resection of the tumour with tracheal reconstruction was planned.
Adult ; Asthma ; diagnosis ; Biopsy ; Bronchoscopy ; Diagnosis, Differential ; Diagnostic Errors ; Dyspnea ; diagnosis ; etiology ; Female ; Follow-Up Studies ; Humans ; Neurilemmoma ; diagnosis ; surgery ; Radiography, Thoracic ; Reconstructive Surgical Procedures ; Respiratory Sounds ; diagnosis ; etiology ; Tomography, X-Ray Computed ; Trachea ; diagnostic imaging ; pathology ; surgery ; Tracheal Neoplasms ; diagnosis ; surgery

OBJECTIVETo study the expression of stromal cell derived factor-1(SDF-1) in the airway and to investigate the role of SDF-1 receptor antagonist AMD3100 intervention in rats with asthma.

METHODSThirty Sprague-Dawley rats were randomly divided into three groups: normal control and asthma with and without AMD3100 intervention. The rat model of asthma was prepared by aerosolized ovalbum (OVA) challenge. The AMD3100 intervention group was administered with AMD3100 of 50 μg 30 minutes before challenge every other day, for 10 times. The characteristic airway inflammation and alterations of airway structures were observed by hemetoxylin and eosin staining. The levels of interleukin 4 and interleukin 5 in whole lung homogenates were measured using ELISA. RT-PCR was used to evaluate the expression of SDF-1 mRNA in the lung.

RESULTSThe airway wall thickness in the untreated asthma group was greater than that in the control and the AMD3100 intervention groups (P<0.05). The levels of interleukin 4 and interleukin 5 in whole lung homogenates in the AMD3100 intervention group were lower than those in the untreated asthma group (P<0.05). The expression of SDF-1 mRNA in the untreated asthma group was higher than that in the control and the AMD3100 intervention groups (P<0.05).

CONCLUSIONSSDF-1 may be associated with airway inflammation and remodeling in rats with asthma. AMD3100 may reduce the airway inflammation and improve airway remodeling by inhibiting the bioactivity of SDF-1.

Animals ; Asthma ; drug therapy ; etiology ; metabolism ; Chemokine CXCL12 ; analysis ; antagonists & inhibitors ; genetics ; physiology ; Female ; Heterocyclic Compounds ; pharmacology ; Interleukin-4 ; analysis ; Interleukin-5 ; analysis ; Lung ; metabolism ; pathology ; RNA, Messenger ; analysis ; Rats ; Rats, Sprague-Dawley ; Receptors, CXCR4 ; antagonists & inhibitors

OBJECTIVETo investigate the roles of FIZZ1 and NOTCH1 in the pathogenesis of asthma and the effect of rosiglitazone on airway remodeling.

METHODSForty-five healthy 6 to 8-week-old Sprague-Dawley rats were randomly divided into a control group and asthma groups with and without rosiglitazone treatment. The paraffin slices of lung tissues were made to assess the histological changes. a-SMA protein, a specific marker of airway remodeling, in lung tissues was measured by immunohistochemistry. FIZZl-mRNA and NOTCH1-mRNA expression in lung tissues was measured by RT-PCR.

RESULTSThe characteristic changes of airway remodeling were observed in the untreated asthma group. The histological changes in the airway were less severe in the rosiglitazone treated asthma group. Positive a-SMA staining, FIZZl-mRNA and NOTCH1-mRNA were highly expressed in peribronchial lung sections isolated from the untreated asthma group. Rosiglitazone treatment decreased significantly the expression of a-SMA protein, FIZZl-mRNA and NOTCH1-mRNA compared with the untreated asthma group, but the expression of a-SMA protein, FIZZl-mRNA and NOTCH1-mRNA in the rosiglitazone treated asthma group remained higher than the control group. a-SMA expression was positively correlated with FIZZl-mRNA (r=0.826, P<0.01) and NOTCH1-mRNA expression (r=0.9, P<0.01). FIZZl-mRNA expression was positively correlated with NOTCH1-mRNA expression (r=0.76, P<0.01).

CONCLUSIONSFIZZl and NOTCH1 may induce an increase in a-SMA expression. FIZZl and NOTCH1 play a critical role in the process of airway remodeling. Rosiglitazone treatment may inhibit airway remodeling in asthmatic rats.

Actins ; Airway Remodeling ; Animals ; Asthma ; etiology ; pathology ; Lung ; metabolism ; pathology ; Male ; Nerve Growth Factor ; genetics ; physiology ; RNA, Messenger ; analysis ; Rats ; Rats, Sprague-Dawley ; Receptor, Notch1 ; genetics ; physiology

OBJECTIVEThe role of air pollution on asthma can not be ignored, diesel exhaust particles (DEP) in the air is one of the most important pollutants. This study aimed to investigate the effect and mechanism of DEP inhaled on immediate reaction in the asthma rats.

METHODSixty male Wistar rats of "Clean" grade, 6 - 7 week-old, with an average weight of (140 +/- 20) g were used in this study. The rats were randomly divided into 6 groups, 10 in each. Group A was treated with normal saline attack as a negative control, Group B with ovalbumin attack as a positive control. After ovalbumin attack, groups C, D, E, F continued to inhale DEP for 1 week, 2 weeks, 3 weeks and 4 weeks, respectively. The concentration of DEP was 200 microg/ml, the animals were subjected to inhalation of ultrasound nebulized DEP for 30 min per day. One week after all the attacks were concluded, Group A was stimulated with normal saline for 30 min, other groups were stimulated with ovalbumin. Then the airway resistance was determined with multi-channel signal acquisition and processing system and compared. The changes in neutrophils, eosinophils, and other inflammatory cells of BALF and the pathological changes in lung tissue, including epithelial cells loss, the inflammatory cells infiltration around the airway, basement membrane fibrosis, goblet cell hyperplasia etc. were observed. The concentration of IL-5 and gamma-interferon in the lung tissues, and the changes of serum IgE etc. were determined.

RESULTAirway resistance values of group A, B, C, D, E, F after ovalbumin excitation for 30 min were (3.56 +/- 0.21), (7.06 +/- 0.63), (6.46 +/- 0.38), (7.47 +/- 0.33), (8.87 +/- 0.61), (11.00 +/- 0.69) cm H2O/(ml.s). No airway hyperresponsiveness occurred in group A, while Groups B, C, D, E, F had higher airway resistance than group A, group E and F had higher airway resistance than that of group B, the differences were statistically significant. And the airway resistance was different in each group among 0 min, 10 min, 20 min and 30 min (F = 160.646, 148.901, 162.204, 156.186, P < 0.01 for both). The time of DEP inhalation and the airway resistance was positively correlated (r = 0.948, P < 0.01); IgE concentrations of the serum between groups B, C, D, E, F was not significantly different (P > 0.05), but higher than that of group A (F = 2.639, P < 0.01). The infiltrated inflammatory cells included eosinophils and lymphocytes, etc. The percentages of neutrophil(%) were (4.3 +/- 2.0), (9.7 +/- 5.2), (10.3 +/- 5.6), (13.0 +/- 5.2), (42.6 +/- 18.3), (55.3 +/- 6.9). The groups E and F had higher percentage than Group A and Group B (F = 114.226, P < 0.01). The percentages of eosinophils(%) were 0, (11.9 +/- 3.8), (15.8 +/- 6.3), (13.0 +/- 4.9), (21.1 +/- 5.6), (27.1 +/- 4.8). The difference between Groups B, C, D, E, F and Group A was statistically significant. There was significant difference between groups C, D, E, F and group B (F = 46.462, P < 0.05); Lung tissue biopsy in group A showed that the epithelial cells were intact, no inflammatory cells infiltrations were found around the airways, instead, mainly ciliated columnar epithelial cells and only a small number of goblet cells were seen without basement membrane fibrosis. With the inhalation of DEP, the epithelial cells showed gradual necrosis, disruption and loss, goblet cells showed hyperplasia, and infiltrations with inflammatory cells were seen around the airway. In the lung tissue, concentrations of IL-5 in group B, C, and E were (12.8 +/- 2.8), (17.1 +/- 5.2), (18.6 +/- 4.2) pg/mg, the difference between groups C, E and group B was statistically significant (F = 4.236, P < 0.01), the difference in gamma-interferon concentration among all groups was not statistically significance (F = 1.185, P > 0.05).

CONCLUSIONDEP inhalation increased the airway responsiveness of asthma rats in immediate reaction, promoted the lung epithelial cell loss, inflammatory cell infiltration, basement membrane fibrosis and goblet cell hyperplasia.

Air Pollutants ; adverse effects ; Airway Resistance ; Animals ; Asthma ; immunology ; metabolism ; pathology ; Disease Models, Animal ; Hypersensitivity, Immediate ; etiology ; Immunoglobulin E ; blood ; Interferon-gamma ; metabolism ; Interleukin-5 ; metabolism ; Lung ; metabolism ; pathology ; Male ; Rats ; Rats, Wistar ; Vehicle Emissions

Reactive oxygen species (ROS) performs a pivotal function as a signaling mediator in receptor-mediated signaling. However, the sources of ROS in this signaling have yet to be determined, but may include lipoxygenases (LOXs) and NADPH oxidase. The stimulation of lymphoid cells with TNF-alpha, IL-1beta, and LPS resulted in significant ROS production and NF-kappaB activation. Intriguingly, these responses were markedly abolished via treatment with the LOXs inhibitor nordihydroguaiaretic acid (NDGA). We further examined in vivo anti-inflammatory effects of NDGA in allergic airway inflammation. Both intraperitoneal and intravenous NDGA administration attenuated ovalbumin (OVA)-induced influx into the lungs of total leukocytes, as well as IL-4, IL-5, IL-13, and TNF-alpha levels. NDGA also significantly reduced serum levels of OVA-specific IgE and suppressed OVA-induced airway hyperresponsiveness to inhaled methacholine. The results of our histological studies and flow cytometric analyses showed that NDGA inhibits OVA-induced lung inflammation and the infiltration of CD11b+ macrophages into the lung. Collectively, our findings indicate that LOXs performs an essential function in pro-inflammatory signaling via the regulation of ROS regulation, and also that the inhibition of LOXs activity may have therapeutic potential with regard to the treatment of allergic airway inflammation.
Animals ; Antioxidants/metabolism ; Asthma/complications/metabolism/pathology/physiopathology ; Bronchial Hyperreactivity/drug therapy/pathology ; Bronchial Provocation Tests ; Bronchoalveolar Lavage Fluid/cytology ; Cells, Cultured ; Drug Evaluation, Preclinical ; Humans ; Inflammation/*etiology/metabolism ; Jurkat Cells ; Lipoxygenase/*physiology ; Lipoxygenase Inhibitors/pharmacology/therapeutic use ; Lymphocytes/drug effects/metabolism ; Male ; Mice ; Mice, Inbred BALB C ; Nordihydroguaiaretic Acid/pharmacology/therapeutic use ; Reactive Oxygen Species/*adverse effects/*metabolism