Bicuculline inhibits airway remodeling in a murine model of chronic asthma / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of bicuculline, a selective GABAA receptor antagonist, on airway remodeling in the murine model of chronic allergen-induced asthma.</p><p><b>METHODS</b>Forty BALB/C mice were randomized into 4 groups, namely the control group, asthmatic model (induced by ovalbumin sensitization and challenge) group, budesonide inhalation group and bicuculline inhalation group. The mice were sacrificed 24 h after the last ovalbumin inhalation, and the lungs were lavaged with PBS and the total cells, eosinophils and lymphocytes counts were examined. Periodic acid-Schiff (PAS) staining was used for counting mucin-positive goblet cells in the lung tissue, and Masson Trichrome staining was used to evaluate collagen deposition. GABAARbeta2 and VEGF were quantified by immunohistochemistry.</p><p><b>RESULTS</b>The numbers of the total cells, eosinophils and lymphocytes counts in BALF were significantly greater in the bicuculline group than in the control and budesonide groups (P<0.01), but comparable to those in the asthmatic model group (P>0.05). The airway collagen deposition in the bicuculline group was comparable to that in the control and budesonide group (P>0.05), but was significantly less than that in the asthmatic model group (P<0.05). Significant differences were found in the airway histological mucus index between the bicuculline group and the other 3 groups (P<0.05). The airway GABAARbeta2-positive cell percentage in the bicuculline group was significantly greater that those in the control and budesonide (P<0.01 and 0.05), but similar with that in the asthmatic model group (P>0.05). The percentage of pulmonary perivascular VEGF-positive cells in the bicuculline group was significantly greater in the control and budesonide groups (P<0.01 and P<0.05), but comparable to that in the asthmatic model group (P>0.05).</p><p><b>CONCLUSION</b>GABAARbeta2 is expressed in both the airway epithelium and smooth muscles. Bicuculline inhalation can effectively suppress collagen deposition with a stronger inhibitory effect on mucus hypersecretion than budesonide.</p>

Validity of Asthma Control Test in Chinese patients / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>So far, in China, there has been no effective or easy procedure to define the control of asthma. This study assesses the validity of Asthma Control Test in Chinese patients.</p><p><b>METHODS</b>Three questionnaires (Asthma Control Test, Asthma Control Questionnaire and the 30 second asthma test) were administered to 305 asthma patients from 10 teaching hospitals across China. Spirometry was also used. Asthma specialists rated the control of asthma according to patients' symptoms, medications and forced expiratory volume in first second. The patients were divided into noncontrolled group and controlled group according to the specialists' rating. Reliability, empirical validity and screening accuracy were conducted for Asthma Control Test scores. Screening accuracy was compared among 3 questionnaires. The patients' self rating and the specialists' rating were also compared.</p><p><b>RESULTS</b>The internal consistency reliability of the 5-item Asthma Control Test was 0.854. The correlation coefficient between Asthma Control Test and the specialists' rating was 0.729, which was higher than other instruments. Asthma Control Test scores discriminated between groups of patients differing in the percent predicted forced expiratory volume in first second (F = 26.06, P < 0.0001), the specialists' rating of asthma control (F = 88.24, P < 0.0001) and the Asthma Control Questionnaire scores (F = 250.57, P < 0.0001). Asthma Control Test showed no significant difference with Asthma Control Questionnaire in the percent correctly classified, while the percent correctly classified by Asthma Control Test was much higher than 30 second asthma test. The patients' self rating was the same as assessment of the specialists (t = 0.65, P = 0.516).</p><p><b>CONCLUSION</b>The Asthma Control Test is an effective and practicable method for assessing asthma control in China.</p>

Effects of Astragalus membranaceus in promoting T-helper cell type 1 polarization and interferon-gamma production by up-regulating T-bet expression in patients with asthma / 中国结合医学杂志

<p><b>OBJECTIVE</b>To explore the effect of Astragalus membranaceus (AM) on T-helper cell type 1 (Thl) specific transcription factor T-box expressed in T cells (T-bet) expression and Thl/Th2 equilibrium.</p><p><b>METHODS</b>The levels of T-bet mRNA in peripheral blood mononuclear cells (PBMCs) from 15 patients with asthma and 15 healthy subjects were determined by reverse transcription-polymerase chain reaction (RT-PCR). PBMCs in asthma patients were incubated with AM and then the concentration of interferon gamma (IFN-gamma) and interleukin-4 (IL-4) in the supernate before and after AM intervention were determined by ELISA. The numbers of CD4 + CCR3 + and CD4 + CCR5 + cells were counted by flow cytometry.</p><p><b>RESULTS</b>The expression of T-bet mRNA and the level of IFN-gamma were lower, but level of serum IL-4 was higher in asthma patients when compared with those in healthy subjects respectively. After AM (60 microg/ml) intervention, the former two parameters raised and showed a positive correlation between them, while the level of IL-4 was decreased. The mean percentage of CD4 + CCR3 + cells in asthma patients was significantly higher but that of CD4 + CCR5 + cells was lower when compared with those in healthy subjects respectively. After AM intervention, the abnormal change in the two indexes was improved to certain extent, showing a reversing status of Th2 polarization.</p><p><b>CONCLUSION</b>AM could increase the expression of T-bet mRNA and Thl cytokines such as IFN-Y, and might reverse the Th2 predominant status in asthma patients.</p>

Relationship between bone marrow-derived CD34 + cells expressing interleukin-5 receptor messenger RNA and asthmatic airway inflammation / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Asthma is clinically related with the degree of eosinophilic inflammation. How asthmatic airway inflammation is affected is still poorly understood. So the effects of bone marrow-derived hematopoietic cells expressing CD(34) (CD(34)(+)) and interleukin-5 (IL-5) receptor messenger RNA (IL-5R mRNA+) on asthmatic airway inflammation were investigated.</p><p><b>METHODS</b>Balb/c mice were sensitized and challenged by ovalbumin (OVA) to establish an asthmatic model while control mice were sensitized and exposed to sterile saline. The mice were killed at different time points after being challenged by OVA and sterile saline. Then, bronchoalveolar lavage fluid (BALF), peripheral blood (PB) and bone marrow (BM) were prepared. Eosinophils in PB (PBEOS) and BALF (BALFEOS), nuclear cells in BALF, PB and BM were counted. By flow cytometry, the percentage of CD(34)(+) cells to nucleated cells in PB, BM and the relative number of CD(34)(+) cells in PB (PBCD(34)(+)) and BM (BMCD(34)(+)) were calculated. Immunocytochemistry and in situ hybridization were used to investigate the hematopoietic cells with co-localized expression of CD(34) and IL-5R mRNA in BM (BMCD34+IL-5R mRNA+). The percentage of BMCD34+IL-5R mRNA+ to BMCD(34)(+) was calculated.</p><p><b>RESULTS</b>Twelve hours after challenge by OVA, BALFEOS and PBEOS in the experimental group were significantly higher than those in the control group (P < 0.01). Twenty-four hours after OVA challenge, BALFEOS, PBEOS and BMCD34+IL-5R mRNA+ were elevated maximally, significantly different from those in the control group (P < 0.01). Forty-eight hours after OVA challenge, BALFEOS and BMCD34+IL-5R mRNA+ were still significantly higher than those of the controls (P < 0.01). The other markers reverted to normal. In 60 mice, BMCD34+IL-5R mRNA+ was closely correlated with the BALEOS, PBEOS, BMCD(34)(+) and BMCD(34)(+) (%) (P < 0.05).</p><p><b>CONCLUSIONS</b>The amount of CD(34)(+) cells expressing IL-5R mRNA increased in the BM of asthmatic model mice, which favors eosinophilopoiesis and eosinophilic airway inflammation. A signal pathway exists between the lungs and the bone marrow, which is involved in the initiation and maintenance of asthmatic airway inflammation.</p>

Effects of glucocorticoid and cysteinyl leukotriene 1 receptor antagonist on CD(34+) hematopoietic cells in bone marrow of asthmatic mice / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Corticosteroids remain the most effective therapy available for asthma. They have widespread effects on asthmatic airway inflammation. However, little is known about the effects of corticosteroids on the production of bone marrow inflammatory cells in asthma. This study observed the effects of glucocorticoid and cysteinyl leukotriene 1 receptor antagonist on CD34+ hematopoietic cells, so as to explore the possible effectiveness of a bone marrow-targeted anti-inflammatory strategy.</p><p><b>METHODS</b>Balb/c mice were sensitized and challenged with ovalbumin (OVA) to establish an asthmatic model. For two consecutive weeks, asthmatic mice were challenged with OVA while being given either prednisone, montelukast, prednisone plus montelukast, or sterile saline solution. The mice were killed 24 hours after the last challenge with OVA, and bronchoalveolar lavage fluid (BALF), peripheral blood, and bone marrow were collected. Eosinophils in peripheral blood and BALF, and nucleated cells in BALF, peripheral blood, and bone marrow were counted. The percentages of CD34+ cells, CD4+ T lymphocytes and CD8+ T lymphocytes among nucleated cells in peripheral blood and bone marrow were counted by flow cytometry. Immunocytochemistry and in situ hybridization were employed to detect expression of CD34 and interleukin (IL)-5Ralpha mRNA (CD34+ IL-5Ralpha mRNA+ cells) among bone marrow hematopoietic cells.</p><p><b>RESULTS</b>Compared with the sterile saline solution group, the number of eosinophils in BALF and peripheral blood, CD34+ cells in peripheral blood and bone marrow, and CD34+ IL-5Ralpha mRNA+ cells in bone marrow of mice from the prednisone and prednisone plus montelukast groups were significantly lower (P < 0.01). The number of eosinophils in BALF from the montelukast group was also significantly lower (P < 0.05).</p><p><b>CONCLUSIONS</b>The results suggest that, in this asthmatic mouse model, prednisone probably inhibits proliferation, differentiation, and migration of CD34+ cells in bone marrow, blocks eosinophilopoiesis in bone marrow, and interferes with eosinophil migration into peripheral blood and subsequent recruitment in the airway. In addition, montelukast may suppress eosinophil infiltration into the lungs of asthmatic mice. However, a significant inhibitory effect of montelukast on the proliferation and migration of CD34+ cells and a cooperating effect with prednisone on bone marrow of asthmatic mice were not observed.</p>