Effects of Aspergillus fumigatus on glucocorticoid receptor and ß2-adrenergic receptor expression in a rat model of asthma.

PURPOSE: Conventional inhaled corticosteroids or ß2-adrenergic receptor agonists do not work well in some asthmatic populations while empirical antifungal therapy has obvious impact on those patients. The study was designed to investigate whether short-term exposure to Aspergillus fumigatus (A. fumigatus) could decrease glucocorticoid receptor (GCR) and ß2-adrenergic receptor (ADRB2) expression in lung tissue of asthmatic rats. MATERIALS AND METHODS: A rat model of chronic asthma was first established by ovalbumin sensitization and challenge. Rats with chronic asthma were then exposed to short-term application of A. fumigatus spores. Airway hyper-responsiveness, eosinophil ratio in bronchoalveolar lavage (BAL) fluid and total IgE in serum were counted in these experimental animals. GCR and ADRB2 expression in the lung were detected and analyzed. Furthermore, the levels of toll-like receptors (TLRs) 2, 3 and 4 in lung tissue were measured. RESULTS: Short-term exposure to A. fumigatus could down-regulate the expression of GCR, aggravate airway hyper-responsiveness and increase the level of TLR2 in rats with asthma. There were no obvious changes in the levels of ADRB2 expression, recruited eosinophils, total IgE, TLR3 and TLR4 after application of A. fumigatus in asthmatic rats. CONCLUSIONS: These findings indicate that A. fumigatus exposure may be involved in glucocorticoids unresponsiveness by down-regulating the expression of GCR in asthmatics. The possibility of A. fumigatus colonization or infection should not be ignored in patients of steroid-resistant asthma.

1α,25-Dihydroxyvitamin D3 Induces Neutrophil Apoptosis through the p38 MAPK Signaling Pathway in Chronic Obstructive Pulmonary Disease Patients.

BACKGROUND: Reduced neutrophil apoptosis plays an important role in the pathogenesis of acute exacerbation chronic obstructive pulmonary disease (AECOPD). The p38 mitogen-activated protein kinase (MAPK) signaling pathway is involved in neutrophil apoptosis. 1α,25-Dihydroxyvitamin D3 (1α,25VitD3) can induce tumor cell apoptosis. The aim of this study was to assess the effects of 1α,25VitD3 on peripheral blood neutrophil apoptosis in AECOPD and examine the role of the p38 MAPK signaling pathway. METHODS: The study enrolled 36 AECOPD patients and 36 healthy volunteers. Venous blood samples were obtained from both groups. Serum 25-hydroxyvitamin D (25-(OH) D) levels in peripheral venous blood were assayed using liquid chromatography-tandem mass spectrometry (LC-MS/MS); the neutrophils were separated and cultured with SB203580 (a p38 inhibitor) and 1α,25VitD3. Neutrophil apoptosis was measured using flow cytometry, and phospho-p38 MAPK protein expression was detected by Western blot. Statistical analysis was performed using analysis of variance. Student's t-test and Pearson's correlation coefficient were used for the between-group differences and correlation analysis, respectively. RESULTS: The 25-(OH) D levels were lower in AECOPD patients than in healthy controls, and the peripheral blood neutrophil apoptosis results were similar. 1α,25VitD3 increased the apoptosis rate and the level of phospho-p38 MAPK in peripheral blood neutrophils of AECOPD patients. SB203580 partly inhibited 1α,25VitD3-induced peripheral blood neutrophil apoptosis and phospho-p38 MAPK overexpression. The 25-(OH) D levels were positively correlated with increased peripheral blood neutrophil apoptosis and phospho-p38 MAPK levels. In addition, expression of the phospho-p38 MAPK protein was also positively correlated with peripheral blood neutrophil apoptosis. CONCLUSION: Our results suggest that 1α,25VitD3 induces peripheral blood neutrophil apoptosis through the p38 MAPK signaling pathway in AECOPD patients.

Role of prostaglandin D2 /CRTH2 pathway on asthma exacerbation induced by Aspergillus fumigatus.

Aspergillus fumigatus is often associated in asthmatic patients with the exacerbation of asthma symptoms. The pathomechanism of this phenomenon has not been fully understood. Here, we evaluated the immunological mechanisms and the role of the prostaglandin D2 / Chemoattractant Receptor-Homologous Molecule Expressed on Th2 Cells (CRTH2) pathway in the development of Aspergillus-associated asthma exacerbation. We studied the effects of A. fumigatus on airway inflammation and bronchial hyper-responsiveness in a rat model of chronic asthma. Inhalation delivery of A. fumigatus conidia increased the airway eosinophilia and bronchial hyper-responsiveness in ovalbumin-sensitized, challenged rats. These changes were associated with prostaglandin D2 synthesis and CRTH2 expression in the lungs. Direct inflammation occurred in ovalbumin-sensitized, challenged animals, whereas pre-treatment with an antagonist against CRTH2 nearly completely eliminated the A. fumigatus-induced worsening of airway eosinophilia and bronchial hyper-responsiveness. Our data demonstrate that production of prostaglandin D2 followed by eosinophil recruitment into the airways via a CRTH2 receptor are the major pathogenic factors responsible for the A. fumigatus-induced enhancement of airway inflammation and responsiveness.

A multicenter, randomized, double-blind, placebo-controlled study to evaluate the efficacy of paclitaxel-carboplatin alone or with endostar for advanced non-small cell lung cancer.

INTRODUCTION: Recombinant human endostatin is a novel inhibitor of tumor angiogenesis that acts specifically on neovascular endothelial cells. Studies have shown that endostar plus vinorelbine-cisplatin chemotherapy could improve objective response rates (ORR) and overall survival (OS) of advanced non-small cell lung cancer (NSCLC) patients. This study is to explore the clinical efficacy of endostar plus paclitaxel-carboplatin (TC) in advanced NSCLC patients. METHODS: A phase II, multicenter, randomized, double-blind, placebo-controlled study was carried out. Patients were randomly assigned to the treatment (TC + endostar) or the control group (TC + placebo). The efficacy was evaluated at the end of each cycle. Follow-up continued until disease progression or death. RESULTS: A total of 126 patients were enrolled, of whom 122 were evaluable, with 61 in each group. ORR was 39.3% in the treatment group versus 23.0% in the control group (p = 0.078), and the disease control rate was 90.2% versus 67.2% (p = 0.004), respectively. The median progression-free survival (PFS) was 7.1 versus 6.3 months (p = 0.522) in the treatment and control groups, the 24-week rate of PFS was 78% versus 59% (p = 0.017), and the median OS was 17.6 versus 15.8 months (p = 0.696), respectively. There were no significant differences, either in the incidence of adverse events or serious adverse events, between the two groups. CONCLUSIONS: In previously untreated, advanced NSCLC patients, treatment with TC plus endostar seemed to improve ORR. However, the differences in PFS or OS between the two groups were not statistically significant. Treatment with TC plus endostar exhibited a good safety profile.

Mastic alleviates allergic inflammation in asthmatic model mice by inhibiting recruitment of eosinophils.

The pathogenesis of allergic asthma is characterized by airway inflammation, eosinophilia, and airway hyperresponsiveness. In the present study, we investigated the anti-inflammatory effects of mastic, obtained from the stem and the leaves of Pistacia lentiscus trees, on allergic asthma. In an ovalbumin-induced mouse asthma model, mastic significantly inhibited eosinophilia, while reducing airway hyperresponsiveness and suppressing the production of inflammatory cytokines (IL-5 and IL-13) as well as chemokines (eotaxin, eotaxin2, and regulated upon activation, normal T-cell expressed and secreted) in bronchoalveolar lavage fluid. Moreover, mastic potently inhibited eotaxin-induced eosinophil chemotaxis in vitro without influencing eotaxin receptor, chemokine receptor 3, expression. These results suggest that mastic may contribute to the treatment of inflammatory diseases.

TSLP from RSV-stimulated rat airway epithelial cells activates myeloid dendritic cells.

The respiratory syncytial virus (RSV) is a primary cause of lower respiratory tract infections in children, the elderly and in people who are immune suppressed, and is also the cause for the development of asthma primarily in infants. However, the immunological mechanisms by which RSV enhances allergic sensitization and asthma remain unclear. The aim of this study was to examine the influence of RSV-infected airway epithelial cells on the activation and functions of rat myeloid dendritic cells (mDCs).We found that the exposure of primary rat airway epithelial cells (PRAECs) to RSV induced a rapid (6 h), high (12 h) and persistent (18 h) increase in thymic stromal lymphopoietin (TSLP) mRNA compared with untreated PRAECs. TSLP protein expression was also enhanced by RSV infection. Functional maturation of mDCs was induced by RSV-treated PRAECs, as shown by their enhanced levels of OX40L and thymus- and activation-regulated chemokine (TARC) mRNAs, which increased the expressions of major histocompatibility complex II (MHCII) and CD86 costimulatory molecules and promoted enhanced T-cell proliferation in mixed lymphocyte reactions. These activities were inhibited in cocultures with RSV-infected RTECs (rat tracheal epithelial cells, an immortalized cell strain) that had been pretreated with TSLP-targeted small interfering RNA. These results suggest that RSV can induce epithelial cells to produce TSLP, which in turn promotes the maturation of mDCs that might support Th2 cell polarization.

[A multicenter, randomized, double-blind, placebo-controlled safety study to evaluate the clinical effects and quality of life of paclitaxel-carboplatin (PC) alone or combined with endostar for advanced non-small cell lung cancer (NSCLC)].

OBJECTIVE: To analyze the efficacy and quality of life and safety for paclitaxel and carboplatin (TC) and TC combined with endostar in the treatment of advanced non-small cell lung cancer (NSCLC). METHODS: This is a prospective, multicenter, randomized, double-blind, placebo-controlled clinical study. A total of 126 cases of untreated advanced NSCLC were enrolled in this study. There were 63 patients in the TC control arm and TC combined endostar arm, respectively. All enrolled patients were continuously followed-up for disease progression and death. RESULTS: The objective response rate (ORR) of TC combined with endostar arm was 39.3%, and that of TC control arm was 23.0%, P = 0.078. The progression-free survival rates for TC combined with endostar arm and TC control arm were 78.3% and 58.8%, respectively, in 24 weeks (P = 0.017). The hazard ratio for the risk of disease progression was 0.35 (95%CI 0.13 to 0.90, P = 0.030). The median time to progression (TTP) of the TC combined with endostar arm was 7.1 months and TC arm 6.3 months (P > 0.05). The follow-up results showed that the median survival time (mOS) of the TC + Endostar arm was 17.6 months; (95%CI 13.4 to 21.7 months), and the TC + placebo arm 15.8 months (95%CI 9.4 to 22.9 months) (P > 0.05). The quality of life scores (LCSS patient scale) after treatment of the TC combined with endostar arm was improved, and that of the TC group was improved after completion of two cycles and three cycles of treatment. The quality of life scores compared with baseline after the completion of one cycle treatment was significantly improved for both the TC combined with endostar arm (P = 0.028 and), and TC arm (P = 0.036). It Indicated that TC combined with endostar treatment improved the patient's quality of life in the early treatment. The difference of adverse and serious adverse event rates between the two groups was not significant (P > 0.05). CONCLUSIONS: Compared with TC alone treatmrnt, TC combined with endostar treatment can reduce the risk of disease progression at early time (24 weeks), increase the ORR, and can be used as first-line treatment for advanced NSCLC. The TC combined with endostar treatment has good safety and tolerability, improves the quality of life, and not increases serious adverse effects and toxicity for patients with advanced NSCLC.

Chronic intranasal administration of Aspergillus fumigatus spores leads to aggravation of airway inflammation and remodelling in asthmatic rats.

BACKGROUND AND OBJECTIVE: Epidemiological evidence indicates a close link between exposure to fungi and deterioration of asthma. However, the role of fungi as an exogenous precipitant for initiation and progression of asthma has been incompletely explored. In this study, the effects of Aspergillus fumigatus exposure on airway inflammation and remodelling in a rat model of chronic asthma were investigated. METHODS: The rat model of chronic asthma was established by systemic sensitization and repeated challenge with ovalbumin (OVA). The asthmatic rats were exposed to chronic intranasal inhalation of A. fumigatus spores. Changes in airway inflammation, remodelling and BHR were measured after exposure to the fungus. RESULTS: Chronic inhalation of A. fumigatus spores elevated the production of T helper 2 (Th2) cytokines, increased the concentration of total serum IgE, and resulted in the recruitment of eosinophils and lymphocyte infiltration into the airways of asthmatic rats. Goblet cell hyperplasia, mucus hyperproduction and subepithelial collagen deposition were also induced by inhalation of the fungus. The remodelling changes induced by inhalation of the fungus paralleled the changes in BHR in this rat model of asthma. CONCLUSIONS: Chronic exposure to A. fumigatus aggravated Th2 airway inflammation, promoted airway remodelling and increased BHR in OVA-sensitized and -challenged rats.

Rapid non-genomic effects of glucocorticoids on oxidative stress in a guinea pig model of asthma.

BACKGROUND AND OBJECTIVE: Glucocorticoids (GC) may exert therapeutic effects in asthma by a rapid non-genomic mechanism. The lungs of asthmatic patients are exposed to oxidative stress, which is believed to be critical in the pathogenesis of asthma. The aim of this study was to investigate whether GC exert a rapid non-genomic effect on oxidative stress in asthmatic guinea pigs. METHODS: The guinea pig asthma model was used to assess inhibitory effects of budesonide (BUD) on oxidative stress. BAL fluid (BALF), trolox equivalent antioxidant capacity and lung manganese superoxide dismutase (MnSOD) activity were measured by spectrophotometry. Superoxide anion production was measured by cytochrome c reduction assay. RESULTS: Oxidative stress occurred within minutes following antigen challenge and BUD reduced the severity of oxidative stress in asthmatic guinea pigs within 15 min. BUD significantly decreased BALF trolox equivalent antioxidant capacity and lung MnSOD activity, as compared with those of vehicle-treated asthmatic guinea pigs (P < 0.05). Additionally, BUD rapidly inhibited in vitro superoxide anion production by BALF cells and bronchi harvested from sensitized animals. These rapid effects were not blocked by the GC receptor antagonist RU486 and/or the protein synthesis inhibitor cycloheximide. CONCLUSIONS: BUD reduced oxidative stress in a guinea pig model of asthma by a rapid non-genomic mechanism. These data suggest new mechanisms whereby GC treatments may benefit asthma.