To investigate the role of histamine in airway remodeling, 50 healthy guinea pigs were divided into 5 groups: control group: nebulized inhalation of distilled water for 8 weeks; asthma model group: nebulized inhalation of ovalbumin (OVA) for 8 weeks after sensitization; continued asthma model group: nebulized inhalation of OVA for 14 weeks after sensitization; histamine group: nebulized inhalation of OVA for 14 weeks after sensitization and histamine was added in the last 6 weeks; antagonist group: nebulized inhalation of OVA for 14 weeks after sensitization and histamine receptor antagonists were added in the last 6 weeks. For each group, the concentration of histamine, sodium ion (Na(+)), chlorine ion (Cl(-)), arterial partial pressure of oxygen (PaO2), arterial partial pressure of carbon dioxide (PaCO2), pH, actual bicarbonate (AB), standard bicarbonate (SB) in serum, and thickness of airway mucosa, base membrane and smooth muscle were measured and compared with each other. The results showed that: (1) the concentration of histamine in serum and the thickness of airway increased, the following order was, the control group, the asthma model group, the continued asthma model group and histamine group (P<0.01); and the concentration of histamine in serum and the thickness of airway of antagonist group was lower than that of the continued asthma model group (P<0.05, 0.01). (2) PaO2 of the asthma model group was lower than that of the normal control group (P<0.01); PaO2, pH, AB, SB decreased, the following order was, the asthma model group, the continued asthma model group and the histamine group (P<0.01); and PaO2, pH, AB, SB of the antagonist group was higher than that of the continued asthma model group (P<0.01); but for PaCO2, the order was converse (P<0.01); For the concentration of Na(+) and Cl(-) in serum, there was no difference among these groups. It is concluded that: (1) Histamine is one of the mediators in the airway remodeling of asthma. (2) Histamine receptor antagonists may play a role in preventing and treating airway remodeling. (3) There is a negative correlation between the PaO2, pH and the wall thickness of the airway (P<0.01), while a positive correlation between the PaCO2, anion gap (AG) and the wall thickness of the airway (P<0.01).
Airway Remodeling ; physiology ; Animals ; Asthma ; chemically induced ; physiopathology ; Guinea Pigs ; Histamine ; physiology ; Histamine Antagonists ; pharmacology ; Male ; Ovalbumin ; Random Allocation

AIMTo explore the physiopathological mechanisms of airway injury and the effect on the airway responsiveness of rat by inhaled sulfur dioxide(SO2).

METHODSSixteen SD male rats were divided randomly into 2 groups (n = 8): the control group and SO2 group. The control group was exposed o pure air. SO2 group was exposed to SO2 of the content 1.0 mg/(m(3) x h) 6h daily for consecutive 3 d. At 4th day, we determined the airway responsiveness, collected the bronchoalveolar lavage fluid (BALF), plasma and lung tissue. Then we counted the total cellular score in BALF, measured the plasma SP content and made the immunohistochemistry staining on the lung tissue (HE and SP methods).

RESULTSCompared with the control group, the total cellular score in BALF and plasma SP content in SO2 group's increased significantly ( P < 0.01). HE staining showed there were a great deal of inflammatory cells infiltration under the tunica mucosa bronchiorum; and SP immunohistochemistry staining indicated there were significant changes in numbers of SP-IR positive fibers of SO2group.

CONCLUSIONExposure to low concentration of SO2 would injure healthy rat's airway, and induce airway hyperresponsiveness, neurogenic inflammation is one of its critical pathophysiological mechanisms.

Air Pollutants ; adverse effects ; Animals ; Asthma ; chemically induced ; Bronchi ; drug effects ; innervation ; physiopathology ; Bronchial Hyperreactivity ; chemically induced ; physiopathology ; Bronchitis ; chemically induced ; Bronchoalveolar Lavage Fluid ; cytology ; Male ; Nerve Fibers ; drug effects ; physiology ; Neurogenic Inflammation ; chemically induced ; physiopathology ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Substance P ; blood ; Sulfur Dioxide ; adverse effects

OBJECTIVETo establish a method for measurement of airway resistance (sRaw) and reactivity in guinea pigs.

METHODSMethacholine spray at gradient concentrations was given to guinea pigs. PC100 was defined as the concentration of methacholine when the sRaw doubled in the guinea pigs using a double-chamber plethysmograph. The time for the recovery of PC100 resistance to baseline levels was measured. The sRaw and PC100 were measured twice on days 1 and 15 (4 time points) in the guinea pigs before and after OVA challenge.

RESULTSPC100 in a normal guinea pig airway was shown to recover the baseline level within 1 h. Double-chamber plethysmographical measurement of the sRaw and PC100 in normal guinea pigs did not show significant differences between the time points [sRaw: 3.25-/+0.67, 3.33-/+0.58, 3.30-/+0.56, and 3.32-/+0.75 cm H2O.s; log2PC100: 8.48-/+0.94, 8.64-/+1.04, 8.56-/+0.67, and 8.64-/+0.60, respectively, P>0.05]. The sRaw and airway reactivity were significantly increased in guinea pigs challenged with OVA [sRaw: 7.08-/+1.82 vs 2.87-/+0.53 cmH2O.s, P<0.01; log2PC100: 6.64-/+1.26 vs 8.48-/+1.17, P<0.01].

CONCLUSIONA double-chamber plethysmography for measurement of sRaw and airway reactivity in guinea pig is established successfully.

Airway Resistance ; Animals ; Asthma ; chemically induced ; physiopathology ; Bronchial Hyperreactivity ; etiology ; physiopathology ; Guinea Pigs ; Male ; Methacholine Chloride ; Plethysmography ; instrumentation ; methods ; Random Allocation

BACKGROUND/AIMS: Asthma is characterized by airway hyperresponsiveness, inflammation, and remodeling. Peroxisome proliferator-activated receptors have been reported to regulate inflammatory responses in many cells. In this study, we examined the effects of intranasal rosiglitazone on airway remodeling in a chronic asthma model. METHODS: We developed a mouse model of airway remodeling, including smooth muscle thickening, in which ovalbumin (OVA)-sensitized mice were repeatedly exposed to intranasal OVA administration twice per week for 3 months. Mice were treated intranasally with rosiglitazone with or without an antagonist during OVA challenge. We determined airway inflammation and the degree of airway remodeling by smooth muscle actin area and collagen deposition. RESULTS: Mice chronically exposed to OVA developed sustained eosinophilic airway inflammation, compared with control mice. Additionally, the mice developed features of airway remodeling, including thickening of the peribronchial smooth muscle layer. Administration of rosiglitazone intranasally inhibited the eosinophilic inflammation significantly, and, importantly, airway smooth muscle remodeling in mice chronically exposed to OVA. Expression of Toll-like receptor (TLR)-4 and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kappaB) was increased in the OVA group and decreased in the rosiglitazone group. Co-treatment with GW9660 (a rosiglitazone antagonist) and rosiglitazone increased the expression of TLR-4 and NF-kappaB. CONCLUSIONS: These results suggest that intranasal administration of rosiglitazone can prevent not only air way inf lammation but also air way remodeling associated with chronic allergen challenge. This beneficial effect is mediated by inhibition of TLR-4 and NF-kappaB pathways.
Actins/metabolism ; Administration, Inhalation ; Airway Remodeling/*drug effects ; Animals ; Anti-Asthmatic Agents/*administration & dosage ; Asthma/chemically induced/*drug therapy/metabolism/physiopathology ; Chronic Disease ; Collagen/metabolism ; Disease Models, Animal ; Female ; Lung/*drug effects/metabolism/physiopathology ; Mice, Inbred BALB C ; NF-kappa B/metabolism ; Ovalbumin ; PPAR gamma/agonists/metabolism ; Pneumonia/chemically induced/physiopathology ; Pulmonary Eosinophilia/chemically induced/prevention & control ; Signal Transduction/drug effects ; Thiazolidinediones/*administration & dosage ; Toll-Like Receptor 4/metabolism

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

OBJECTIVETo investigate the expressions of PPAR-gamma/PGC-1alpha and Nrf2/gamma-GCS-h in lung of guinea pigs with bronchial asthma, and to explore the roles of them.

METHODSForty adult male guinea pigs were randomly divided into 4 groups: the control group (group A), asthmatic group ( group B), dexamethasone group (group C) and rogridone group (group D), 10 guinea pigs in each group. The asthmatic model was established by the ovalbumin challenge method. Expressions of PPAR-gamma/PGC-1alpha and Nrf2/gamma-GCS-h mRNA in lung tissue were assayed by in situ hybridization. Expressions of PPAR-gamma/PGC-1alpha and Nrf2/gamma-GCS-h protein were detected by immunohischemistry and by Western blot.

RESULTSIn situ hybridization showed that the expressions of PPAR-gamma/PGC-1alpha and Nrf2/gamma-GCS-h mRNA in lung tissue were the lowest in group B and the comparison among groups showed statistical significant (all P < 0.01). Immunohistochemistry and Western blot indicated that the value of PPAR-gamma/PGC-1alpha and Nrf2/gamma-GCS-h protein in lung tissue were the lowest in group B, and expressed primarily in nucleus, the differences being statistically significant (all P < 0.01). There was positive correlation between PPAR-gamma and PGC-1. gamma-GCS-h mRNA also positively correlated between PPAR-gamma/PGC-1alpha and Nrf2 in nucleus, and the expression of Nrf2 was also positively correlated with PPAR-gamma/ PGC-1alpha.

CONCLUSIONIn acute asthmatic models induced by ovalbumin, the expressions of PPAR-alpha/PGC-1alpha and Nrf2/gamma-GCS-h were decreased, and PPARgamma/PGC-1alpha could up-regulate the expressions of Nrf2/gamma-GCS-h to increase the antioxidant defense of tissues, thus being implicated that PPARgamma/PGC-1alpha might play important roles in the pathogenesis and prevention of asthma.

Animals ; Asthma ; chemically induced ; physiopathology ; Glutamate-Cysteine Ligase ; genetics ; metabolism ; Guinea Pigs ; Lung ; metabolism ; Male ; NF-E2-Related Factor 2 ; genetics ; metabolism ; Ovalbumin ; PPAR gamma ; genetics ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Transcription Factors ; genetics ; metabolism

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

OBJECTIVEThrough the establishment of mouse' ovalbumin- sensitized asthmatic model and the observation of the 8-Isoprostane of plasm, to evaluate the therapeutic effects of arsenolite on asthmatic mice.

METHODForty-two healthy Kunming male mice were randomly divided into control group and experience groups, the latter were treated with dexamethasone, arsenolite. Lung function were tested, 8-isoprostane of plasm and WBC of BALF were measured.

RESULTLung function improved after treating with dexamethasone or arsenolite. The WBC of asthmatic mice were significantly higher than those in control group, and decreased after treating with dexamethasone or arsenolite; 8-Isoprostane of plasm in asthmatic mice was higher than that of control group, and decreased after treating with dexamethasone or arsenolite.

CONCLUSIONThere is oxidant stress status in asthmatic mice. Arsenolite could lighten airway obstruction, reduce airway high response and redress oxidant stress status in asthmatic mice.

Animals ; Anti-Asthmatic Agents ; pharmacology ; Arsenicals ; pharmacology ; Asthma ; blood ; chemically induced ; physiopathology ; Bronchoalveolar Lavage Fluid ; cytology ; Dinoprost ; analogs & derivatives ; blood ; Leukocyte Count ; Male ; Materia Medica ; pharmacology ; Mice ; Ovalbumin ; Oxides ; pharmacology ; Random Allocation ; Respiratory Function Tests

BACKGROUND: Although benzalkonium chloride (BAC)-induced bronchoconstriction occurs in patients with bronchial asthma, BAC-containing nebulizer solutions are still being used in daily practice in Korea. The aim of this study was to evaluate the effects of inhaled aqueous solutions containing BAC. METHDOS: Thirty subjects with bronchial asthma and 10 normal controls inhaled up to three 600 microgram nebulized doses of BAC using a jet nebulizer. FEV1 (forced expiratory volume at one second) was measured 15 minutes after each dose. Inhalations were repeated every 20 minutes until FEV1 decreased by 15% or more (defined as BAC-induced bronchoconstriction) or the 3 doses were administered. RESULTS: The percent fall in FEV1 in response to BAC inhalation was significantly higher in asthmatics than in normal subjects (p<0.05). BAC administration in subjects with asthma reached a plateau (maximal effect). BAC-induced bronchoconstriction was found in 6 asthmatics (20%), with two responders after the 2nd inhalation and 4 after the 3rd inhalation. The percent fall in FEV1 in response to the 1st inhalation of BAC was significantly higher in asthmatics with higher bronchial hyperresponsiveness (BHR) than in those with lower BHR. CONCLUSIONS: This study suggests that the available multi-dose nebulized solution is generally safe. However, significant bronchoconstriction can occur at a relatively low BAC dose in asthmatics with severe airway responsiveness.
Adult ; Albuterol/adverse effects ; Asthma/*chemically induced/physiopathology ; Benzalkonium Compounds/*adverse effects ; Bronchial Provocation Tests ; *Bronchoconstriction ; Case-Control Studies ; Detergents/*adverse effects ; Female ; Forced Expiratory Volume ; Health Status Indicators ; Humans ; Male ; Middle Aged ; Risk Factors ; Spirometry

OBJECTIVESan'ao Decoction (, SAD), as a representative Chinese medicine (CM) formula, was chosen to evaluate the effect of airway inflammation and hyperresponsiveness on the lipopolysaccharide (LPS) enhanced asthma model.

METHODSThe asthma model was reproduced in the Balb/C mice sensitized by ovalbumin (OVA), challenged by OVA and LPS. After Balb/C mice's administration of a dose (0.0024 g/kg) of dexamethasone acetate, and three doses (2.2 g/kg, 4.4 g/kg and 8.8 g/kg) of SAD, airway inflammation and responsiveness were observed. The airway inflammation was detected by counting bronchoalveolar lavage fluid (BALF) cells and lung histopathology. Also, differential expressions of interferon-r (IFN-γ), interleukin-4 (IL-4), and IL-5 in the supernatants of BALF were examined. The changes in airway responsiveness indicated by lung resistance (R(L)) and stimulated by acetylcholine (Ach) were determined.

RESULTSSmall-dose SAD hardly inhibit airway inflammation or hyperresponsiveness in the LPS-enhanced asthma, while medium-dose and high-dose SAD significantly inhibited the airway hyperresponsiveness, and to some extent, reduced airway inflammation. Meanwhile, the small-dose, medium-dose, and high-dose SAD promoted Th1-type cytokines (IFN-γ) and reduced Th2-type cytokines (IL-4, IL-5) to different extents, which led to a Th1/Th2 balance.

CONCLUSIONSAD has a good therapeutic effect on airway hyperresponsiveness in the LPS-enhanced asthma model, but its definite influence on airway inflammation is not remarkable.

Animals ; Asthma ; chemically induced ; complications ; drug therapy ; physiopathology ; Bronchial Hyperreactivity ; complications ; drug therapy ; pathology ; Bronchoalveolar Lavage Fluid ; cytology ; Cell Count ; Disease Models, Animal ; Drugs, Chinese Herbal ; therapeutic use ; Female ; Interferon-gamma ; metabolism ; Interleukin-4 ; metabolism ; Interleukin-5 ; metabolism ; Lipopolysaccharides ; Lung ; pathology ; physiopathology ; Mice ; Mice, Inbred BALB C ; Pneumonia ; complications ; drug therapy ; pathology