Effect of cigarette smoke extraction on the expression of found in inflammatory zone 1 in rat lung epithelial L2 cells

Background Found in inflammatory zone 1 （FIZZ1） protein increased in pulmonary epithelial cells and in limited amounts of other lung cells.FIZZ1 increased in murine model of smoke induced chronic obstructive pulmonary disease.However,the direct role of FIZZ1 produced by pulmonary epithelium stimulated with cigarette smoke extraction has not been determined.We examined the expression and function of FIZZ1 in rat lung epithelial L2 cells.Methods The rat lung epithelial L2 cells （CCL 149） were exposed to cigarette smoke extraction,expression of FIZZ1 mRNA was investigated by RT-PCR.Levels of FIZZ1 protein were detected by Western blotting and laser confocal microscope.CCL 149 cells were treated with different concentrations and for different time of recombinant protein FIZZ1.After treatment,the expression levels of interleukin 8 （IL-8） were detected by enzyme-linked immunosorbent assay （ELISA）.Results When CCL 149 cells were exposed to cigarette smoke extraction,FIZZ1 mRNA and protein levels expressed significantly higher than control group.Recombinant protein FIZZ1 promoted the expression of IL-8 in a dose and time dependent manner in a certain range.Conclusions Cigarette smoke extraction activates FIZZ1 at mRNA and protein levels in CCL 149 cells.Recombinant protein FIZZ1 induces the expression of IL-8 and may thus participate in the process of chronic obstructive pulmonary disease airway inflammation and airflow obstruction.Generally,immune cells such as macrophages,neutrophils and lymphocytes are unavoidably involved in airway inflammatory and immune responses to cigarette smoke,but it is still unclear whether their involvement in the pathogenesis of chronic obstructive pulmonary disease is based on the specific expression in lung epithelial cells of FIZZ1.     

Low-intensity aerobic exercise training attenuates airway inflammation and remodeling in a rat model of steroid-resistant asthma

Background Aerobic exercise can improve symptoms,reduce airway inflammation,and even ameliorate airway remodeling in asthmatic animals and patients.However,previous studies have focused mainly on the effect of aerobic exercise on steroid-sensitive asthma （SSA）.The goals of this study were to determine the effect of low-intensity aerobic exercise training on airway hyperresponsiveness,inflammation,and remodeling in a rat model of steroid-resistant asthma （SRA） and to identify the potential mechanisms underlying these effects.Methods Endotoxin-free ovalbumin with or without lipopolysaccharide were applied to establish rat models of SRA and SSA,respectively.Airway hyperresponsiveness,inflammation,remodeling,expression of interleukin （IL）-25,IL-33,thymic stromal lymphopoietin （TSLP）,high mobility group box-1 （HMGB1）,and IL-17 in bronchoalveolar lavage fluid （BALF）,and the role of dexamethasone （DXM） were compared between these two asthmatic rat models.The effect of low-intensity aerobic exercise training and anti-HMGB1 treatment on airway hyperresponsiveness,inflammation,and remodeling in SRA rats also was evaluated.Results SRA rats developed neutrophil-dominated airway inflammation （（29.5±4.1）％ of the total cell numbers in BALF）,whereas SSA rats developed eosinophil-dominated airway inflammation （（24.0±6.1）％ of the total cell numbers in BALF）.Compared with SSA rats,SRA rats had more severe airway hyperresponsiveness,lower levels of IL-25 （（33.6±10.3） vs.（104.8±24.9） pg/ml）,IL-33 （（87.5±25.0） vs.（226.6±40.7） pg/ml）,and TSLP （（1 933.2±899.5） vs.（7 224.0±992.1） pg/ml）,and higher levels of HMGB1 （（21.2±4.5） vs.（5.4±1.6） ng/ml） and IL-17 （（780.5±261.7） vs.（291.4±76.4） pg/ml） in BALF （all P ＜0.05）.However,there was no significant difference in goblet cell hyperplasia,subepithelial collagen thickness,and airway smooth muscle remodeling between the two groups.Compared with control SSA rats,airway hyp     

β-carotene protects rats against bronchitis induced by cigarette smoking

Objective To investigate the protective effects of B-carotene in rats against the development of chronic bronchitis induced by cigarette smoking.Methods Forty-two Male Wistar rats were randomly divided into three study groups: ①control (n =15), animals underwent no treatment; ②cigarette smoking (n = 15), animals developed chronic bronchitis through long-term cigarette smoking twice a day for 75 d; ③β-carotene plus cigarette smoking animals (n =12) were given 1 ml or 15 mg/kg β-carotene orally every day just before cigarette smoking. The levels of IL-6, IL-8, NO, superoxide dismutase (SOD) and lipoperoxide(LPO) in serum, bronchoalveolar lavage fluid (BALF) and lung tissue were measured and the pathological changes to lung tissue were analyzed using light microscopy.Fiesults Long-term cigarette smoking caused an obvious increase in the amount of IL-6, IL-8 and LPO and a sharp decrease in the levels of NO and SOD in smoking animals compared to controls. β-carotene intake reversed all the changes induced by smoking and alleviated the pathological changes caused by chronic bronchitis.Conclusions Quantitative oral intake of B-carotene had protective effects against chronic bronchitis induced by long-term cigarette smoking, which was associated with the increased production of NO,the clearance of some oxidative free radicals (OFR) and the alleviation of chronic inflammation.     

Eosinophil: central mediator of allergic asthma?

Allergic asthma is a chronic disorder characterized by chronic airway inflammation, airway hyperresponsiveness, reversible airway obstruction, airway remodelling and mucus hypersecretion. It has been widely recognized that the infiltration of the lung with increased number of eosinophils is a hallmark of this disease.     

Effect of smoking cessation on airway inflammation of rats with chronic bronchitis

Background Smoking is the major cause of airway inflammation in chronic obstructive pulmonary disease （COPD）, and smoking cessation is regarded as one of the important strategies for prevention and treatment of the inflammation. The inflammation of the chronic airway may be present and deteriorated even if the COPD patients stop smoking. Whether and how early smoking cessation affects the progress of inflammation is still obscure. This study was conducted to find the appropriate time for smoking cessation to terminate the airway inflammation in rats with smoke-induced chronic bronchitis. Methods A rat model of COPD was established by passively inhaling smoke mixture. Fifty-four young male Sprague-Dawley rats were randomly divided into 9 groups with different periods of smoke exposure and different time points of cessation. The inflammation markers to be detected included inflammatory cells in the bronchoalveolar lavage fluid （BALF）, the myeloperoxidose （MPO） activity, the morphologic changes and the expression of ICAM-1 on the airway epithelium. Results When smoking was terminated at early stage, the inflammatory markers and related indexes were different from those of the typical chronic bronchitis group （group M7） （P〈0.01）. The pathologic score of group SC7 （2 weeks of smoking cessation after occurrence of typical chronic bronchitis ） was not different from that of group M7, and the level of ICAM-1 was still up-regulated （compared to group M7, P〉0.05）. Meanwhile, most of inflammatory cells in BALF were neutrophils compared to other groups （P〈0.01）.When smoking was terminated, the MPO activity was significantly lower than that of group M7 （P〈0.01）. Conclusions Smoking cessation at early stage can effectively inhibit the inflammatory reaction of COPD. Once chronic bronchitis occurs, little could be improved by smoking cessation.     

Eosinophil: central mediator of allergic asthma?

Allergic asthma is a chronic disorder characterized by chronic airway inflammation, airway hyperresponsiveness, reversible airway obstruction, airway remodelling and mucus hypersecretion. It has been widely recognized that the infiltration of the lung with increased number of eosinophils is a hallmark of this disease.1     

Linker for activation of T cells contributes to airway inflammation in an asthmatic mouse model

Background Allergic asthma is associated with airway inflammation and hyperresponsiveness caused by dysregulated production of cytokines secreted by allergen-specific helper T-type 2 （Th2） cells. The linker for activation of T cells （LAT） is a membrane-associated adaptor protein, which has been shown to take part in regulating T cell receptor （TCR） signaling and T cell homeostasis. In this study, we established an asthmatic mouse model to examine the changes in LAT levels during allergic airway disease and the effects of LAT transgenic expression on airway inflammation. Methods T cells from mouse lung tissues were isolated from allergen challenged （ovalbumin （OVA）） and control mice, and the purity of these isolated T cells was examined by fluorescence-activated cell sorter （FACS）. Semi-quantitative RT-PCR and Western blotting were used to detect the expression of the LAT gene and LAT protein, respectively. After an intranasally administered mixture of pCMV-HA-LAT plasmid and Lipofectamine 2000, 24 hours before and 72 hours after allergen challenge, the BALF cell count and the differential cytologies were studied. In addition, IL-4 and IFN-γ levels in the BALF were determined by ELISA, and pathological changes in lung tissues were observed. Results LAT protein and mRNA expression were decreased in lung T cells in a mouse model of allergen-induced airway disease. After intranasal administration of pCMV-HA-LAT, histopathological examination of the lungs showed that intervention with LAT overexpression prevented mice from developing airway inflammation, and the number of total cells, eosinophils, neutrophils, and lymphocytes in the BALF was reduced significantly compared with the OVA sensitized and challenged group. In addition, the Th2 cytokine IL-4 decreased, while the Thl cytokine IFN-γ increased compared to the OVA sensitized and challenged group or the OVA sensitized group plus pCMV-HA treatment. Conclusion This study demonstrates that LAT might effectively diminish Th2 cytokine responses, lung histopathological changes and lung inflammation to allergen challenge in a model of expedmentally induced asthma.     

Recombinant adeno-associated virus-mediated inhibiting of interleukin-4 expression in rat model of asthma

Asthma is a chronic disease characterized by reversible airway obstruction, airway hyper- responsiveness, and inflammation of airways. Th2 cells, one sort of CD4+ T lymphocytes, are currently considered to play an important role in the chronic airway inflammation of asthma. Meanwhile, a number of laboratories have clearly established the importance of the Th2-derived cytokine interleukin-4 (IL-4) in mediating the airway inflammatory response. Anti-IL-4 therapy might be beneficial in treatme…     

Corticosteroid resistance in chronic obstructive pulmonary disease: new uses of theophylline

Chronic obstructive pulmonary disease (COPD) is a major global health problem with a rising morbidity and mortality,which is expected to account for about 27％ of tobacco related deaths and is anticipated to move from the fifth to the fourth leading cause of death worldwide from 2002 to 2030.1 COPD is characterized by the abnormal and chronic inflammation induced by cigarette smoking and other inflammatory insults in both small airway and lung parenchyma.2,3 Glucocorticosteroids (also called glucocorticoids,corticosteroids or steroids) are the most effective anti-inflammatory drugs available for the treatment of many chronic inflammatory and immune diseases.4 However,corticosteroids have limited benefit in treating stable COPD5 defined as (relative) steroid insensitivity or resistance6 and may be characteristic of all phenotypes of COPD.Although anti-inflammatory treatments are expected to effectively treat inflammation of COPD,almost all anti-inflammatory approaches risk increasing the extent of infection by blunting host defence mechanisms.Their effectiveness in humans has been limited by various side effects.5 Therefore,it is important to develop a treatment to enhance corticosteroid anti-inflammatory action in COPD.     

Inhibitory effects of sunitinib on ovalbumin-induced chronic experimental asthma in mice

Background Tyrosine kinase signaling cascades play a critical role in the pathogenesis of allergic airway inflammation. Sunitinib, a multitargeted receptor tyrosine kinase inhibitor, has been reported to exert potent immunoregulatory, anti-inflammatory and anti-fibrosis effects. We investigated whether sunitinib could suppress the progression of airway inflammation, airway hyperresponsiveness （AHR）, and airway remodeling in a murine model of chronic asthma.
Methods Ovalbumin （OVA）-sensitized mice were chronically challenged with aerosolized OVA for 8 weeks. Some mice were intragastrically administered with sunitinib （40 mg/kg） daily during the period of OVA challenge. Twelve hours after the last OVA challenge, mice were evaluated for the development of airway inflammation, AHR and airway remodeling. The levels of total serum immunoglobulin E （IgE） and Th2 cytokines （interleukin （IL）-4 and IL-13） in bronchoalveolar lavage fluid （BALF） were measured by ELISA. The expression of phosphorylated c-kit protein in the lungs was detected by immunoprecipitation/Western blotting （IP/WB） analysis.
Results Sunitinib significantly inhibited eosinophilic airway inflammation, persistent AHR and airway remodeling in chronic experimental asthma. It reduced levels of total serum IgE and BALF Th2 cytokines and also lowered the expression of phosphorylated c-kit protein in remodelled airways.
Conclusions Sunitinib may inhibit the development of airway inflammation, AHR and airway remodeling. It is potentially beneficial to the prevention or treatment of asthma.     

Recombinant adeno-associated virus-mediated inhibiting of interleukin-4 expression in rat model of asthma

Asthma is a chronic disease characterized by ,reversible airway obstruction, airway hyperresponsiveness, and inflammation of airways, Th2 cells, one sort of CD4＋ T lymphocytes, are currently considered to play an important role in the chronic airway inflammation of asthma, Meanwhile, a number of laboratories have clearly established the importance of the Th2-dedved cytokine interleukin-4 （IL-4） in mediating the airway inflammatory response, Anti-IL-4 therapy might be beneficial in treatment of chronic asthma.     

Influence of airway inflammatory changes on airway hyperresponsiveness in asthmatics.

The effect of changes of airway inflammation on airway nonspecific reactivity were studied in 29 patients with chronic asthma. Detailed examinations of bronchial lavage (BAL) fluid and airway responses to histamine, propranolol and exercise were performed before and after treatment. The patients treated with steroids had significant improvements in parameters of BAL fluid cells and mediators with consistent changes of decreasing airway reactivities to propranolol and exercise after treatment. Whereas no significant changes occurred in the patients treated with B2-agonist either in inflammatory parameters or airway responses. On the other hand, airway response to histamine changed little in all asthmatic patients. Our study implied that inhibiting the airway inflammation in asthmatics may lead to marked decrease of airway response to non-mediator stimuli but fail to attenuate bronchial hyperresponse to mediator stimuli like histamine.

     

Expressions of tumor necrosis factor-converting enzyme and ErbB3 in rats with chronic obstructive pulmonary disease

Background Chronic obstructive pulmonary disease (COPD) is associated not only with airway inflammation characterized by mucin hypersecretion but also with systemic inflammation. Tumor necrosis factor alpha (TNF-α) is found to take part in systemic inflammation, and ErbB3 plays an important role in mucin hypersecretion of COPD. Since TNF-α converting enzyme (TACE) is involved in the activation of both TNF-α and ErbB3, we established rat models of COPD to investigate the expressions of TACE, TNF-α and ErbB3 and to explore the correlations among TACE,TNF-α and ErbB3 respectively. Methods Thirty Wistar male rats were randomly divided into COPD group (group C, n=10), saline solution parallel group (group P, n=8), and normal control group (group N, n=8). Group C was challenged with passive cigarette smoking and intratracheal instillation of lipopolysaccharide. Six weeks later pulmonary functions were tested, bronchoalveolar fluid and arterial blood gases were assayed, and histopathological evaluations were performed in turn. The expressions of TACE, TNF-α and ErbB3 in lungs of all rats were determined histochemically. Results The expressions of TACE, TNF-α and ErbB3 were significantly higher in group C than in group N (P<0.01). The contents of TNF-α in serum (P<0.01) and bronchoalveolar lavage fluid (BALF) (P<0.01) were elevated more significantly in group C than in group N. A positive correlation existed between TACE and TNF-α (r=0.784, P<0.01) and between TACE and ErbB3 (r=0.526, P<0.01) respectively. Conclusions TNF-α and ErbB3 are involved in the pathogenesis of COPD. TACE contributes to the progress of COPD indirectly through the function of TNF-α and ErbB3.     

Inflammatory responses of the rat lungs in cold-dryness syndrome in the northwest of China

OBJECTIVE:To examine changes in body weight and the lung inflammation factors interleukin-1β(IL-1β),interleukin-8(IL-8),IL-10 and tumor necrosis factor-α(TNF-α) in a rat model of cold-dryness syndrome in Northwest(Xinjiang) China to provide a reference for treating chronic obstructive pulmonary disease(COPD) with local peculiarities.METHODS:The rat COPD model was established by intratracheal instillation of porcine pancreatic elastase(PPE) in combination with cigarette smoking(CS).The rat model of cold-dryness syndrome of COPD in the northwest of China was set up by intratracheal instillation of PPE in combination with CS and environmental cold-dryness stress.The level of IL-1β,IL-8,IL-10 and TNF-α in Bronchoalveolar lavage fluid(BALF) were measured by enzyme-linked immunosorbent assay(ELISA).The data were analyzed using the software SPSS 11.5.RESULTS:1) Body weight was less in the two model groups than that of control group(P<0.01),PPE plus CS cold-dryness group was less than that of PPE plus CS group(P<0.01).2) IL-1β in BALF significantly increased in PPE plus CS and cold-dryness group than that of control group(P<0.01).3) IL-8 and TNF-α in BALF significantly increased in PPE plus CS and cold-dryness group and PPE plus CS group than that of control group(P<0.01).CONCLUSION:Body weight in COPD model rats was reduced compared with controls.Cold-dryness may aggravate such a condition Lung inflammation in the model was mainly manifested by an increase in IL-1β,IL-8 and TNF-α levels,with no change in IL-10 levels.Cold-dryness may aggravate lung inflammation of COPD.     

Effects of aerosolized ketamine on the level of nitric oxide and nitric oxide synthetase in the lung tissue of rat with asthma

Objective： To explore the effects of aerosolized ketamine on the level of nitric oxide and nitric oxide synthetase in the lung tissue in rat asthma model. Methods： Forty SD rats were randomly assigned to five groups： control group （group N）, asthma model group （group A）, two pretreated groups of different concentrations of ketamine （group K1, K2） and dexamethasone group（group D） with eight rats in each group. The rats in group A were sensitized by injection of ovalbumin （OA） together with aluminum hydroxide and bordetella pertussis as adjuvants. Two weeks after the sensitization, aerosolized OA was used to cause asthma. The rats in group K1 and K2 were sensitized with OA as group A , and then exposed to aerosol of ketamine , with the concentration of 25 g/L and 50 g/L respectively. Before using aerosolized OA,the rats in group D were exposed to aerosol of 0.01% dexamethasone .The level of NO2^-/NO3^- in lung tissues, inducible nitric oxide synthetase（iNOS） and constitute nitric oxide synthetase（cNOS） was measured in all groups. Results： The level of NO2^-/NO3^- and the activity of iNOS in lung tissues in group A were signiticantly higher than those in the other groups. The iNOS activity and the level of NO2^-/NO3 ^- in lung tissues were highly positively correlated. Conclusion： NO can induce airway hyperreactivity that may worsen asthma. Aerosolized ketamine can decrease the iNOS expression and reduce the level of NO in the lung tissue in rat asthma model.     

Therapeutic potential of antibodies against interleukin 5 in asthma

Bronchial asthma is characterized by chronic recruitment of eosinophils in the airways. It has been reported that bronchial eosinophil recruitment and activation may even occur in mild-moderate stable asthma and that bronchial epithelium damage and airway responsiveness may be partially associated with the eosinophilic inflammatory reaction.1 There is increasing evidence that the eosinophil-rich bronchial inflammation characteristic of asthma is orchestrated, at least partly,     

Effects of resolvin D1 on inflammatory responses and oxidative stress of lipopolysaccharide-induced acute lung injury in mice

Background A variety of inflammatory mediators and effector cells participate together in acute lung injury,and lead to secondary injury that is due to an inflammatory cascade and secondary diffuse lung parenchyma injury.Inflammation is associated with an oxidative stress reaction,which is produced in the development of airway inflammation,and which has positive feedback on inflammation itself.Resolvin D1 can reduce the infiltration of neutrophils,regulate cytokine levels and reduce the inflammation reaction,and thereby promote the resolution of inflammation.The purpose of this study is to investigate the effects of resolvin D1 on an inflammatory response and oxidative stress during lipopolysaccharide （LPS）-induced acute lung injury.Methods LPS （3 mg/kg） was used to induce the acute lung injury model.Pretreatment resolvin D1 （100 ng/mouse） was given to mice 30 minutes before inducing acute lung injury.Mice were observed at 6 hours,12 hours,1 day,2 days,3 days,4 days and 7 days after LPS was administrated,then they were humanely sacrificed.We collected bronchoalveolar lavage fluid （BALF） and the lung tissues for further analysis.Paraffin section and HE staining of the lung tissues were made for histopathology observations.Parts of the lung tissues were evaluated for wet-to-dry （W/D） weight ratio.tumor necrosis factor （TNF）-α,inter leukin （IL）-1β,IL-10 and myeloperoxidase （MPO） were detected by enzyme-linked immunosorbent assay （ELISA）.A lipid peroxidation malondialdehyde （MDA） assay kit was used to detect MDA.A total superoxide dismutase assay kit with WST-1 was used to analyze superoxide dismutase （SOD）.We determined the apoptosis of neutrophils by Flow Cytometry.A real-time quantitative PCR Detecting System detected the expression of mRNA for heme oxygenase （HO）-1.Results Pretreatment with resolvin D1 reduced the pathological damage in the lung,decreased the recruitment of neutrophils and stimulated their apoptosis.It markedly decreased the expressions of TNF-α,IL-1β and increased the expressions of IL-10,and decreased the production of MDA and increased the expressions of SOD.The mRNA expression of HO-1 was also significantly increased.Conclusions Resolvin D1 displays potent anti-inflammatory actions by regulating cytokines,inhibiting aberrant neutrophil recruitment and stimulating apoptosis of neutrophils.Resolvin D1 can also relieve the injury due to oxidative stress.The mechanisms might be related to increase HO-1 expression.     

Role of extracellular signal-regulated kinase 1/2 in cigarette smoke-induced mucus hypersecretion in a rat model

Background  Airway mucus hypersecretion is an important pathophysiological feature of chronic obstructive pulmonary disease, which is closely associated with cigarette smoking. However, the signal transduction pathway from the cell surface to the nucleus through which cigarette smoke causes upregulation of mucin gene expression is not well known. This study was designed to investigate the role of extracellular signal-regulated Kinase 1/2 (ERK 1/2) in airway mucus hypersecretion induced by cigarette smoke in rats.

Methods  A rat model of airway mucus hypersecretion was induced by exposure to cigarette smoke for 4 weeks．Rats exposed to inhalation of cigarette smoke or normal saline were given an intraperitoneal injection of U0126, a specific MEK1 kinase inhibitor, at doses of 0.25 mg/kg, 0.5 mg/kg and 1 mg/kg for 14 days. Expression of MUC5AC mRNA and protein, ERK 1/2 and phosphorylated-ERK 1/2 (p-ERK 1/2) were detected by RT-PCR, immunohistochemistry and Western blotting.

Results  Cigarette smoke significantly increased airway goblet cells metaplasia, induced the overexpression of MUC5AC mRNA and protein in bronchial epithelia, and increased the ratio of p-ERK 1/2 and ERK 1/2. U0126 significantly attentuated the expression of MUC5AC mRNA and protein induced by cigarette smoke (P <0.05). Moreover, there was a significant positive correlation between the ratio of p-ERK1/2 to ERK1/2 and the expression of MUC5AC mRNA and protein (P <0.05).

Conclusions  Inhibition of ERK 1/2 by U0126 decreased the ratio of p-ERK 1/2 to ERK 1/2 and expression of MUC5AC mRNA and protein. ERK 1/2 may play an essential role in cigarette smoke-induced mucus hypersecretion in vivo.

     

Inflammatory airway features and hypothalamic-pituitary- adrenal axis function in asthmatic rats combined with chronic obstructive pulmonary disease

Background Bronchial asthma （BA） and chronic obstructive pulmonary disease （COPD） are both inflammatory airway diseases with different characteristics. However, there are many patients who suffer from both BA and COPD. This study was to evaluate changes of inflammatory airway features and hypothalamic-pituitary-adrenal （HPA） axis function in asthmatic rats combined with COPD. Methods Brown Norway （BN） rats were used to model These three models were compared and evaluated with the inflammatory airway diseases of BA, COPD and COPD＋BA. respect to clinical symptoms, pulmonary histopathology, airway hyperresponsiveness （AHR）, inflammatory cytokines and HPA axis function. Results The inflammatory airway features and HPA axis function in rats in the COPD＋BA model group were greatly influenced. Rats in this model group showed features of the inflammatory diseases BA and COPD. The expression of inflammatory cytokines in this model group might be up or downregulated when both disease processes are present. The levels of corticotrophin releasing hormone mRNA and corticosterone in this model group were both significantly decreased than those in the control group （P 〈0.05）. Conclusions BN rat can be used as an animal model of COPD＋BA. By evaluating this animal model we found that the features of inflammation in rats in this model group seem to be exaggerated. The HPA axis functions in rats in this model group have been disturbed or impaired, which is prominent at the hypothalamic level.