OBJECTIVETo study the effect and mechanism of arsenic trioxide (As2O3) on apoptosis of pulmonary eosinophiles (PE) in asthmatic guinea-pigs.

METHODSThirty guinea-pigs were divided into 3 groups at random, the control group, the asthmatic group and the As2O3 group. The dosage of As2O3 used was 2 mg/kg. The apoptotic PE were labelled by TdT-mediated dUTP nick end labelling technique, and the PE infiltration and apoptosis were detected quantitatively using computerized image analysis technique.

RESULTSIn the control group, the amount of infiltrating PE was 4.4 +/- 2.5 cells/HP and the PE apoptotic index (AI) was 0.42 +/- 0.08%. In the asthmatic group, the amount increased (P < 0.01) and AI decreased significantly (P < 0.01). After the asthmatic animals had been treated with As2O3, the two parameters changed reversedly significantly (P < 0.01), and there was a significantly negative correlation between them (r = -0.949, P < 0.01).

CONCLUSIONThe PE apoptosis abnormality is one of the important mechanisms that cause bronchial asthma, As2O3 could alleviate the airway inflammation through promoting PE apoptosis and lower PE infiltration. Low dose of As2O3 is proved to be effective with relative safety, it also has potential value in treating asthma.

Animals ; Apoptosis ; drug effects ; Arsenicals ; pharmacology ; Asthma ; chemically induced ; pathology ; Eosinophils ; pathology ; Guinea Pigs ; Image Processing, Computer-Assisted ; Lung ; pathology ; Male ; Ovalbumin ; Oxides ; pharmacology ; Random Allocation

The development of a serological marker for early diagnosis of isocyanate-induced occupational asthma (isocyanate-OA) may improve clinical outcome. Our previous proteomic study found that expression of vitamin D-binding protein (VDBP) was upregulated in the patients with isocyanate-OA. In the present study, we evaluated the clinical relevance of VDBP as a serological marker in screening for isocyanate-OA among exposed workers and its role in the pathogenesis of isocyanate-OA. Three study groups including 61 patients with isocyanate-OA (group I), 180 asymptomatic exposed controls (AECs, group II), 58 unexposed healthy controls (NCs, group III) were enrolled in this study. The baseline serum VDBP level was significantly higher in group I compared with groups II and III. The sensitivity and specificity for predicting the phenotype of isocyanate-OA with VDBP were 69% and 81%, respectively. The group I subjects with high VDBP (> or = 311 microg/ml) had significantly lower PC20 methacholine levels than did subjects with low VDBP. The in vitro studies showed that TDI suppressed the uptake of VDBP into RLE-6TN cells, which was mediated by the downregulation of megalin, an endocytic receptor of the 25-hydroxycholecalciferol-VDBP complex. Furthermore, toluene diisocyanate (TDI) increased VEGF production and secretion from this epithelial cells by suppression of 1,25-dihydroxycholecalciferol [1,25(OH)2D3] production. The findings of this study suggest that the serum VDBP level may be used as a serological marker for the detection of isocyanate-OA among workers exposed to isocyanate. The TDI-induced VEGF production/secretion was reversed by 1,25(OH)2D3 treatment, which may provide a potential therapeutic strategy for patients with isocyanate-OA.
Adult ; Animals ; *Asthma/blood/chemically induced/pathology ; Cell Line ; Epithelial Cells ; Female ; Gene Expression/drug effects ; Humans ; Isocyanates/toxicity ; Male ; Middle Aged ; *Occupational Diseases/blood/chemically induced/pathology ; Rats ; Toluene 2,4-Diisocyanate/toxicity ; Vitamin D-Binding Protein/*blood

AIMTo investigate the effect of inhalation of cyclosporin (CsA) on antigen-induced airway inflammation in Sprague-Dawley rats.

METHODSRats were sensitized with antigen (ovalbumin, OA). After two weeks, the sensitized rats were pretreated with aerosol CsA (5, 10, 20 g x L(-1)), once per day for 7 days. Then, the sensitized rats were challenged with OA (10 g x L(-1), once per day) for 2 days at day 20 after sensitization. The number of eosinophils in bronchoalveolar lavage fluid (BALF) and peripheral blood, histological changes of lung tissue, and TNF-alpha content in BALF were investigated.

RESULTSInhalation of CsA significantly reduced the number of eosinophils in BALF and peripheral blood, inflammatory infiltration and tissue edema of lung tissue, decreased the content of TNF-alpha in BALF.

CONCLUSIONInhalation of CsA inhibited airway inflammation in rats, and the mechanism is related to inhibition of TNF-alpha release.

Administration, Inhalation ; Animals ; Asthma ; chemically induced ; metabolism ; pathology ; Bronchoalveolar Lavage Fluid ; chemistry ; Cyclosporine ; administration & dosage ; pharmacology ; Eosinophils ; pathology ; Female ; Immunosuppressive Agents ; pharmacology ; Leukocyte Count ; Lung ; pathology ; Male ; Ovalbumin ; Rats ; Rats, Sprague-Dawley ; Tumor Necrosis Factor-alpha ; metabolism

Silica nanoparticles (SNPs) are widely used in many scientific and industrial fields despite the lack of proper evaluation of their potential toxicity. This study examined the effects of acute exposure to SNPs, either alone or in conjunction with ovalbumin (OVA), by studying the respiratory systems in exposed mouse models. Three types of SNPs were used: spherical SNPs (S-SNPs), mesoporous SNPs (M-SNPs), and PEGylated SNPs (P-SNPs). In the acute SNP exposure model performed, 6-week-old BALB/c female mice were intranasally inoculated with SNPs for 3 consecutive days. In the OVA/SNPs asthma model, the mice were sensitized two times via the peritoneal route with OVA. Additionally, the mice endured OVA with or without SNP challenges intranasally. Acute SNP exposure induced significant airway inflammation and airway hyper-responsiveness, particularly in the S-SNP group. In OVA/SNPs asthma models, OVA with SNP-treated group showed significant airway inflammation, more than those treated with only OVA and without SNPs. In these models, the P-SNP group induced lower levels of inflammation on airways than both the S-SNP or M-SNP groups. Interleukin (IL)-5, IL-13, IL-1beta and interferon-gamma levels correlated with airway inflammation in the tested models, without statistical significance. In the mouse models studied, increased airway inflammation was associated with acute SNPs exposure, whether exposed solely to SNPs or SNPs in conjunction with OVA. P-SNPs appear to be relatively safer for clinical use than S-SNPs and M-SNPs, as determined by lower observed toxicity and airway system inflammation.
Animals ; Asthma/*chemically induced/pathology ; Female ; Inflammation/*chemically induced/pathology ; Interferon-gamma/analysis ; Interleukins/analysis ; Lung/drug effects/*pathology ; Mice, Inbred BALB C ; Nanoparticles/*adverse effects/chemistry ; Ovalbumin/adverse effects ; Polyethylene Glycols/adverse effects/chemistry ; Silicon Dioxide/*adverse effects/chemistry ; Surface Properties

OBJECTIVETo explore the role of Toll like receptor 4(TLR4) in the asthmatic rat airway smooth muscle cell (ASMCs) proliferation and apoptosis.

METHODSEstablished rat model of asthma,isolated and cultured rat ASMCs in asthma, using methods of small molecule RNA interference technology and lipofection method, for small molecule RNA-TLR4 transfection, detected proliferation of ASMCs by MIT minim colorimetry, apoptosis of ASMCs by TUNNEL, the expression of TLR4 protein and mRNA were detected by Western blot and RT-PCR in cells.

RESULTSThe proliferation of ASMCs in TNF-alpha group were significantly higher than that in control group and siRNA-TLR4 transfection group and TNF-alpha + siRNA-TLR4 transfection group respectively and the proliferation of ASMCs in siRNA-TLR4 transfction group was lower than that in control group. The apoptosis rate of ASMCs in TNF-alpha group was lower than that in control group, siRNA-TLR4 transfection group and TNF-alpha + siRNA-TLR4 transfection group respectively and the apoptosis rate of ASMCs in siRNA-TLR4 transfection group and TNF-alpha + siRNA-TLR4 transfection group were significantly higher than those in control group. The mRNA and protein expression of TLR4 in control group and TNF-alpha group were significantly higher than those in siRNA-TLR4 transfection group and TNF-alpha + siRNA-TLR4 transfection group. The mRNA and protein expression of TLR4 in TNF-alpha group were significantly higher than those in control group (P < 0.01).

CONCLUSIONActivation of TLR4 may contribute to asthmatic airway smooth muscle cell proliferation, inhibiting apoptosis and play an important role in airway remodeling in asthma.

Airway Remodeling ; Animals ; Apoptosis ; Asthma ; chemically induced ; pathology ; physiopathology ; Cell Proliferation ; Cells, Cultured ; Male ; Myocytes, Smooth Muscle ; pathology ; RNA, Messenger ; genetics ; metabolism ; RNA, Small Interfering ; genetics ; Rats ; Rats, Sprague-Dawley ; Toll-Like Receptor 4 ; genetics ; metabolism ; Transfection

This work was designed to explore the role of extracellular signal-regulated kinase 1/2 (ERK1/2) signaling pathway in migration of bronchial smooth muscle cells (BSMCs) of chronic asthmatic rats. To make chronic asthma model, Wistar rats underwent ovabumin (OVA) injection and eight-week inhalation. BSMCs were cultured in vitro. The expression of ERK1/2 in BSMCs was analyzed by immunocytochemistry, Western blot and RT-PCR. Migration of BSMCs was detected by both plate test and Boyden cell test. Results showed: (1) With Western blot technique, the ratio of p-ERK1/2 to total ERK1/2 in chronic asthmatic group was obviously higher than that in the control group (0.55 +/- 0.05 vs 0.48 +/- 0.04, n=10, P<0.01). (2) With RT-PCR, the relative A values of ERK1 and ERK2 mRNA in airways of chronic asthmatic rats were 1.83 +/- 0.24 and 1.07 +/- 0.11, respectively, which were significantly increased compared with that in the control group (0.58 +/- 0.14 and 0.51 +/- 0.12, n=10, P<0.01). (3) In plate test, the migration of BSMCs of chronic asthmatic rats was 2.9 times of that in the control group and reached 5.0 times by epidermal growth factor (EGF) stimulation, but decreased to 1.7 times by 30 mumol/L PD98059. (4) In Boyden cell test, the migration of BSMCs of chronic asthmatic rats was 1.9 times of that in the control group, and reached 3.1 times by EGF stimulation, but decreased to 1.45 times by 30 mumol/L PD98059. Our results indicate that the migration ability of BSMCs of chronic asthmatic rats increases, and ERK1/2 signaling pathway may play an important role in this process.
Animals ; Asthma ; chemically induced ; physiopathology ; Bronchi ; pathology ; Cell Movement ; physiology ; Cells, Cultured ; Male ; Mitogen-Activated Protein Kinase 1 ; metabolism ; physiology ; Mitogen-Activated Protein Kinase 3 ; metabolism ; physiology ; Myocytes, Smooth Muscle ; pathology ; Ovalbumin ; Rats ; Rats, Wistar ; Signal Transduction ; physiology

OBJECTIVETo investigate the effect of prostaglandin D2 receptor antagonists on the airway inflammation in rats with asthma.

METHODSForty male SD rats were randomly divided into four groups: Group A (normal control), Group B (asthma group), Group C (CRTH2 antagonist BAYu3405 treatment group), Group D (DP1 antagonist BWA868C treatment group). Asthma was induced by ovalbumin (OVA) challenge. The rats in each group were sacrificed 24 h after the last challenge of OVA.DP1/CRTH2 receptors on eosinophils (EOS) were measured by radiological binding assay (RBA). The left lungs were used for histological examinations and bronchoalveolar lavage fluid (BALF) was collected from the right lungs. The total cell numbers, EOS absolute count and differential cell counts in BALF were performed. Serum concentrations of IL-4, 5 and IFN-gamma were measured by ELISA.

RESULTSRats in BAYu3405 treatment group showed profoundly decreased infiltrates of EOS and lymphocytes in the wall of bronchus when compared with those of asthma group and BWA868C treatment group. Serum concentrations of IFN-gamma in rats of BAYu3405 treatment group increased, but IL-4 and IL-5 decreased significantly when compared with those in rats of asthma group and BWA868C treatment group (P<0.01), and BALF EOS count was decreased significantly (P<0.01). Peripheral blood EOS count was higher than that in rats of normal control group, but was not significantly different from that in rats of asthma group and BWA868C treatment group. The combining capacity of CRTH2 and DP total combining capacity on EOS in asthma group, BAYu3405 treatment group and BWA868C treatment group were significantly higher than those in Group A (P<0.01). There was no significant difference in DP1 among all the groups (P>0.05).

CONCLUSIONCRTH2, but not DP1 antagonist can effectively ameliorate airway inflammation in rats with asthma.

Animals ; Asthma ; chemically induced ; drug therapy ; pathology ; Bronchi ; immunology ; pathology ; Carbazoles ; pharmacology ; therapeutic use ; Inflammation ; drug therapy ; Male ; Ovalbumin ; Prostaglandin D2 ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Receptors, Immunologic ; antagonists & inhibitors ; Receptors, Prostaglandin ; antagonists & inhibitors ; Sulfonamides ; pharmacology ; therapeutic use

AIM: To evaluate the effect of Qi'ao Deocoction (QAD) on the inflammation and hyperresponsiveness of asthma mice. METHODS: 120 Balb/C mice were randomly divided into six groups: normal group, model group, dexamethasone group, high dose QAD group, medium dose QAD group and low dose QAD group. The asthma model was reproduced in Balb/C mice sensitized by ovalbumin, challenged by OVA and LPS. The mice of the normal group were sensitized, challenged and intranasally instilled by PBS. On day 28-34, 6.7, 13.4 and 26.8 g · kg(-1) Qi'ao Decoction were administrated; 0.002 4 g · kg(-1) dexamethasone solution was given to the dexamethasone group; normal and model groups were given the same amount of normal saline. Bronchoalveolar lavage fluid, airway hyperresponsiveness, lung histopathology and cytokines were then collected and analyzed. RESULTS: Compared with normal group, total cellular score, the number of macrophages, lymphocytes, eosinophils and neutrophils of model group significantly increased (P < 0.01). Compared with model group, the administration of dexamethasone induced a significant decrease in eosinophils and neutrophils (P < 0.05, P < 0.01). The number of eosinophils, which plays an important role in airway inflammatory reaction of asthma, of the three QAD groups all decreased (P < 0.01). RL before and after Ach (5 mg · mL(-1)) stimulation in the model group both overtook that in the normal group (P < 0.01). Compared with model group, dexamethasone group, high dose QAD group, medium dose QAD group and low dose QAD group groups all had significantly lower RL before and after Ach stimulation (P < 0.01). Normal pulmonary histopathology was found in the normal group. In the model group, mice exhibited marked increases in inflammatory cell infiltration, mostly including neutrophils and macrophages, perivascular inflammation and thickened alveolus wall (P < 0.01). Dexamethasone application mitigated inflammation around the bronchi (P < 0.05). These histopathological changes were ameliorated in the three decoction groups (P < 0.01, P < 0.05). In addition, alveolus and airway wall lesions of medium dose QAD group and high dose QAD group were reduced, the number of inflammatory cells infiltrated around the walls decreased, no clear degeneration of bronchial epithelial cells was found, and exudates in bronchi declined in different degrees. Compared with normal group, IFN-γ and IL-12 of model group significantly decreased, while IL-4 increased, showing statistic difference (P < 0.05). Compared with model group, IFN-γ and IL-12 level of dexamethasone group went up too, but IL-4 declined (P < 0.05). The level of IFN-γ of medium dose QAD group and high dose QAD group both increased; IL-4 and IL-12 of medium dose group were found significant differences (P < 0.05); but none of the cytokines of low dose QAD group showed statistical significance (P > 0.05). CONCLUSION QAD can significantly inhibit airway inflammation and airway hyperresponsiveness of mice with severe asthma induced by ovalumin and lipopolysaccharide, adjust the balance of cytokines, and improve lung histopathological condition. So, it exhibits great effect on severe asthma.
Animals ; Asthma ; chemically induced ; drug therapy ; immunology ; pathology ; Drugs, Chinese Herbal ; administration & dosage ; Female ; Humans ; Interleukin-12 ; immunology ; Interleukin-4 ; immunology ; Lipopolysaccharides ; adverse effects ; immunology ; Lung ; immunology ; pathology ; Mice ; Mice, Inbred BALB C ; Ovalbumin ; adverse effects ; immunology

OBJECTIVETo study the anti-asthmatic effect of sodium ferulate (SF) and its mechanism in guinea pig asthmatic model.

METHODSGuinea pigs were sensitized with ovalbumin as animal asthmatic model and treated with 3 different concentration of SF for 8 days. Levels of endothelin (ET) and nitric oxide (NO) in blood and lung tissue, and eosinophil (EOS) in blood and bronchoalveolar lavage fluid (BLAF) was counted at the end of trial.

RESULTSSF could significantly lower the ET content and increase the NO concentration in serum and lung tissue, reduce the number of EOS in blood and BLAF (P < 0.05, P < 0.01). Stronger effect was showed in the high dose group.

CONCLUSIONMechanism of anti-asthmatic action of SF might be to increase NO concentration, lower ET content, alleviate EOS infiltration.

Animals ; Anti-Asthmatic Agents ; pharmacology ; Asthma ; blood ; chemically induced ; Bronchoalveolar Lavage Fluid ; cytology ; Coumaric Acids ; pharmacology ; Endothelin-1 ; blood ; Eosinophils ; pathology ; Female ; Guinea Pigs ; Male ; Nitric Oxide ; blood ; Ovalbumin

Vascular endothelial growth factor (VEGF) is a multi-functional cytokine involved in inflammation, repair and angiogenesis in asthmatic airway. This study aimed to evaluate the role of VEGF in immediate bronchoconstriction induced by TDI inhalation, and in chronic TDI-asthma patients. 11 newly diagnosed TDI-asthma patients (group I), 12 chronic TDI-asthma patients with persistent asthma symptoms followed for >4 yr and 15 unexposed healthy controls were enrolled. In group I, induced sputum and serum were collected before and 7 hr after placebo- and TDI-bronchoprovocation test (BPT). In group II, induced sputum and serum were collected every 2 yr. VEGF levels were measured by ELISA. There were no significant differences in sputum and serum VEGF levels between patients and controls. Before and after placebo and TDI-BPT, no significant changes were noted in sputum and serum VEGF levels of group I. In group II patients, sputum VEGF showed variable changes at 1-yr, then decreased significantly at 2-yr (p<0.05), while serum VEGF showed variable changes at 2-yr, which decreased significantly at 4-yr (p<0.05). These results suggest that VEGF may play a minor role in immediate bronchoconstriction after TDI-BPT. In chronic TDI-asthma, VEGF may be involved to 2 yr after the diagnosis and the contribution may decrease after then.
Adult ; Asthma/*chemically induced/*metabolism ; Bronchi/pathology ; Enzyme-Linked Immunosorbent Assay ; Exercise ; Human ; Methacholine Chloride/pharmacology ; Middle Aged ; Placebos ; Sputum/*metabolism ; Support, Non-U.S. Gov't ; Time Factors ; Toluene 2,4-Diisocyanate/*pharmacology ; Vascular Endothelial Growth Factor A/*biosynthesis/metabolism