Objective To observe the eotaxin expression of rat airway smooth muscle cells ( ASMCs) induced by serum from asthmatic rats, and explore the possible mechanism. Methods ASMCs isolated fromrat tracheas were cultured in vivo. Then they were treated with serum from asthmatic rats, or treated with serum and dexamethasone simultaneously. The level of eotaxin protein in supernatant and eotaxin mRNA in ASMCs were measured by ELISA and reverse transcription-polymerase chain reaction. The expression of cAMP in ASMCs was examined by radioimmunoassay. Results After the treatment with sensitized serum, the eotaxin level in supernatant and mRNA expression in ASMCs were significantly higher [ ( 107. 09 ±7. 12) ng/L vs. ( 0. 63 ±0. 56) ng/L, P lt; 0. 05; 1. 39 ±0. 04 vs. 0. 05 ±0. 01, P lt;0. 05] , and the level of cAMP in ASMCs was significantly lower compared with the control group [ ( 17. 58 ±3. 62) ng/L vs. ( 32. 39 ±3. 36) ng/L, P lt; 0. 05] . After intervened by the sensitized serum and dexamethasone simultaneously, the protein and mRNA expressions of eotaxin were lower compared with those intervened by sensitized serumalone [ ( 64. 18 ±4. 04) ng/L and 0. 77 ±0. 19] . The level of eotaxin in supernatant was negatively correlated with cAMP level in ASMCs ( r = - 0. 788, P lt; 0. 01) . Conclusions There is anautocrine function in ASMCs as inflammatory cells after stimulation with sensitized serum. Eotaxin may play an important roll in the pathogenesis of asthma via a cAMP-dependent pathway.
Objective To investigate the expression of stromal cell derived factor-1 ( SDF-1) and the effects of budesonide suspension for inhalation ( Pulmicort Respules) in mice with asthma. Methods Thirty Kunming female mice were randomly divided into three groups, ie. a control group, an asthma group, and a pulmicort treatment group. The asthma group and the pulmicort treatment group were sensitized with ovalbumin ( OVA) by a combination of intraperitoneal injection and repeated OVA intranasal challenges to establish mouse asthma model. The pulmicort treatment group received 100μL pulmicort by intranasal administration before OVA challenge. The immunohistochemistry was used to estimate the expression of SDF-1 in lung tissues. HE staining and Wright-Giemsa staining method were used to assess inflammatory infiltration in the airway and bronchoalveolar lavage fluid ( BALF) respectively. Results The expression of SDF-1 in the asthma group increased significantly compared with the control group ( 0.48 ±0.03 vs. 0.21 ± 0.02, Plt;0.05) , and significantly decreased after the intervention with pulmicort ( 0.29 ±0.01 vs. 0.48 ± 0.03, Plt; 0.05 ) . Compared with control group, the infiltration of inflammatory cells in airway was significantly enhanced in the asthma group, and attenuated in the pulmicort treatment group. The total number of inflammatory cells and eosinophil, lymphocyte, neutrophil counts in BALF increased significantly in the asthma group compared with the control group, and decreased significantly after pulmicort intervention. Conclusion SDF-1 may play an important role in the recruitment of inflammatory cells in asthmatic airway and pulmicort may relieve airway inflammation by decreasing the expression of SDF-1.
Objective To investigate the relevance and changes of mucosal immunity in asthma rats’lung, nose and intestine. Methods Twenty Wistar rats were randomly divided into a normal group and an asthma group. Asthma rat model was established by sensitization and challenge with ovalbumin. CD4 + ,CD8 + , eotaxin protein and its mRNA in rats’lung tissues, rhinal and intestinal mucosa were measured by immunohistochemical methods and situ hybridization. The content of sIgA in bronchoalveolar lavage fluid ( BALF) , nasopharyngeal washings and intestinal mucus supernatant were detected by enzyme-linked immunosorbent assay. Results Compared with the normal group, the levels of CD4 + , CD8 + in rats’lung tissues, rhinal and intestinal mucosa, the expression of eotaxin protein and mRNA in rats’lung tissues, the content of sIgA in nasopharyngeal washing, and the expression of eotaxin protein in intestinal mucosa were significantly higher in the asthma group( P lt; 0. 05) . There were no significant differences of other indices between the two groups. In the normal group, the eotaxin protein expression had a negative correlationbetween lung tissue and rhinal mucosa( r = - 0. 572, P = 0. 008) , and a positive correlation between intestinal and rhinal mucosa( r=0. 638, P =0. 002) . The eotaxin mRNA expression had a positive correlation between lung tissue and rhinal mucosa( r= 0. 502, P = 0. 024) , and a positive correlation between intestinaland rhinal mucosa( r=0. 594, P =0. 006) . In the asthma group, such a correlation was not found except the eotaxin protein expression which had a negative correlation between lung tissue and intestinal mucosa( r =- 0. 448, P = 0. 048) . Conclusions Mucosal immunity in lung, nose and intestine remains a dynamic balance. The balance of mucosal immunity is destroyed in asthma.
Objective To determine the airway wall thickness at the segmental and subsegmental levels in patients with bronchial asthma and eosinophilic bronchitis ( EB) by high resolution CT scanning,and evaluate its relationship with airway hyperresponsiveness. Methods High resolution CT scanning was performed in 14 subjects with asthma,15 subjects with EB, 15 subjects with cough variant asthma ( CVA) ,and 14 healthy volunteers. Total airway and lumen diameter, total airway cross sectional area and lumen area which corrected by body surface area ( BSA) were measured. The percentage of airway wall area to total airway cross sectional area ( WA% ) and wall thickness to airway diameter ratio ( T/D) were calculated for the right upper lobe apical segmental bronchus ( RB1) and all airways clearly visualized with a transverse diameter of 1-6 mm. Results T/D/BSA and WA% in the asthma patients were all significantly higher than those in the subjects with EB, CVA and healthy volunteers. T/D/BSA and WA% in the EB patients were significantly higher than the healthy volunteers, and similar with the CVA patients. Al /BSA in the patientswith asthma and CVA was less than the subjects with EB and the healthy volunteers. However, Al /BSA in the EB patients was similar with the healthy volunteers. Conclusions The airway wall thickness and remodeling can be measured and assessed by high resolution CT. Airway wall thickness and remodeling inEB patients are milder than asthma patients, which may be associated with airway hyperresponsiveness that presents in asthma but not in EB.
Objective To determine if the therapeutic response to an inhaled corticosteroid is attenuated in individuals with asthma who smoke.Methods 38 outpatients with chronic stable asthma who visited during March 2008 and January 2009 were enrolled in the study. 23 cases were nonsmokers and 15 cases were smokers. All of them were treated by daily inhaled budesonide, and β2 agonist when necessary.They were required to record symptoms and peak expiratory flow every day on an asthmatic diary card. Thepatients were followed 28 days. ACT score, asthma-symptom score, Asthma Control Test ( ACT) score,pulmonary function, and peak expiratory flow were compared between the non-smoking and the smoking asthmatic patients. Results All of the patients had statistically significant increases in ACT score, mean morning and night PEF, mean forced expiratory volume in 1 second, and a significant decrease in asthmasymptom score after budesonide treatment compared with before. There were significantly greater changes inany of these parameters in the non-smokers than in the smokers. Conclusions Active cigarette smoking impairs the efficacy of short term inhaled corticosteroid treatment in asthma. This finding has important implications for the management of patients with asthma who smoke.
Objective To study the clinical application of the GOLD/GINA criteria and the Spanish guideline in the diagnosis of asthma-COPD overlap syndrome (ACOS). Methods Patients with stable COPD were consecutively enrolled in the study. Clinical data were collected, lung function with bronchodilator test and peak expiratory flow (PEF) were performed, and peripheral blood eosinophils, total IgE, and sputum inflammatory cells were measured. Those overlap with asthma were identified by the 2 different criteria, and the prevalence and features of ACOS were compared. Results Among 104 cases of stable COPD, 24 (23.1%) and 10 (9.6%) were identified as ACOS by the GOLD/GINA criteria and the Spanish guideline, respectively; the latter 10 cases were all included in the former 24. For the GOLD/GINA criteria, the most common features were symptoms triggered by exercise or emotions, variable airflow limitation, family history of asthma, and other allergic conditions. Mean diurnal PEF variation≥10% was evident in 11 cases (45.8%, 11/24), while bronchodilator test was positive in 16 cases (66.7%, 16/24). For the Spanish guideline, the most common features were diagnosis of asthma before 40, other allergic diseases, positive bronchodilator test on 2 occasions. Conclusions The GOLD/GINA criteria may be more sensitive for the diagnosis of ACOS, and do not need sophisticated lab tests, which may be more applicable for clinical use. The Spanish guideline is restrictive, and therefore may lead to under-diagnosis.
Objective To investigate the clinical manifestations of two common obstructive airway inflammatory diseases [ chronic obstructive pulmonary disease ( COPD) and asthma] in elderly patients for proper diagnosis and treatment of COPD complicated with asthma.Methods 102 elderly patients diagnosed with either COPD or asthma, who visited the Guangzhou Institute of Respiratory Disease fromOctober 2010 to March 2011, were recruited for the study. Comparisons of clinical manifestation, pulmonary function tests ( PFTs) , chest CT and sputum cytological tests were carried out between the patients with asthma-only,COPD-only, and COPD complicated with asthma. Results Of all 102 patients,18 were diagnosed as asthmaonly ( 17. 6% ) , 36 as COPD complicated with asthma ( 35. 3%) , and 48 as COPD-only ( 47. 1% ) . The patients with COPD-only had longer history of present illness in which most had a history of exposure to cigarette smoking. 91. 7% complained of cough as the first symptom, 80% showed severe impairment in PFTs. Among these patients, sputum neutrophilic granulocytes were ( 78. 3 ±5. 1) % , which was significantly higher than the other two groups ( P lt; 0. 05) . Glucocorticosteroid treatment was less effective in thesepatients. In the patients with COPD complicated with asthma, half were smokers, and cough was the first symptom in 63. 9% subjects and wheezing was the first symptom in rest. About 60% had severely impaired PFTs, and these patients responded to glucocorticosteroid better than the COPD-only patients. In the asthmaonlygroup, most complained of wheezing as the first symptom and had better PFTs. However, sputum eosinophilic granulocyte was as high as ( 13. 5 ±3. 1) % . They responded to glucocorticosteroid effectively.Conclusions COPD and asthma were both obstructive airway inflammatory diseases, but pulmonary function and responses to glucocorticosteroid therapy were different. It is necessary to understand the severity and mechanism of airway function impairment in order to improve the proper diagnosis and treatment of asthmaand COPD in elderly.
Objective By using small interfering RNAs ( siRNAs) specific for spleen tyrosine kinase ( Syk) , to evaluate the role of Syk in maturation of bone marrow-derived dendritic cells. Methods The fragments of 21-23 bp siRNAs specific for mice Syk were chemo synthesized and transfected into the asthmatic murine bone marrow-derived dendritic cells ( BMDCs) by Lipofectamine 2000 transfection system for 48 hours. Then BMDCs were co-cultured with T cells from the normal mice spleen for 48 hours. The cytokines including IL-4, IL-13, IL-2 and INF-γin supernatant were detect by ELISA. The expression of Syk protein was measured by Western Blot to determine whether the Syk gene was silenced. Results The expression of Syk protein was obviously decreased in the siRNA-interference group. The secretions of IL-4 and IL-13 were significantly inhibited by siRNA interference ( P lt; 0. 05) , but the secretions of IL-2 and INF-γwere not interfered signficantly ( P gt;0. 05) . Conclusion Syk specific siRNA fragments can block the antigen presentation function of dendritic cells and block the activation and differentiation of T cells.
Objective To investigate the effects of down-regulating of Rfng gene ( 1, 3-Nacetylglucosaminyltransferases) in lung CD4 + T cells of asthmatic rat model by small interfering RNA ( siRNA) and explore the role of Rfng in pathogenesis of asthma. Methods An asthmatic rat model was established by OVA sensitization and challenge. Total T cells were isolated from lung tissue of asthmatic rats, and CD4 + T lymphocytes were purified using magnetic beads. CD4 + T lymphocytes were transfected by siRNA targeting Rfng gene. The mRNA and protein expressions of Rfng were detected by quantitative PCR and Western blot. Quantitative PCR was performed to determine the mRNA levels of Th1 /Th2 cytokines and related genes including IL-12, IFN-γ, IL-4, IL-5, T-bet, and GATA3. ELISA was performed to determine the concentrations of IL-12, IFN-γ, IL-4, and IL-5 in supernatant. Results The mRNA and protein expression of Rfng in RNAi group decreased significantly. IL-12, IFN-γ, T-bet increased and while IL-4, IL-5, and GATA3 decreased significantly. The concentrations of IL-12 and IFN-γ in the supernatant increased significantly, while IL-4 and IL-5 decreased significantly. Conclusions Down regulation of Rfng affects T cell differentiation. It is presumed that Fringe contribute to the pathogenesis of asthma.
Objective To evaluate the clinical value and safety of adenosine monophosphate( AMP)bronchoprovocation test in patients with asthma. Methods Sixty asthmatics, including 19 cases with uncontrolled asthma, 22 with partially controlled asthma, and 19 with controlled asthma were enrolled. Twenty-four healthy volunteers were enrolled as control and 20 patients with upper respiratory tract infection ( URI) were also included. AMP bronchoprovocation test ( AMP-BPT) was performed. PD20 FEV1-AMP lt;40 mg was set as a cut-off value of positive response to AMP. Positive rate, sensitivity, specificity, accuracy and adverse reactions of AMP-BPT were evaluated. Eleven cases with uncontrolled asthma and 12 cases with partially controlled asthma were followed up with AMP-BPT three months and six months after inhaledcorticosteroids treatment. Asthma symptom scores were recorded a week early before each challenge. The correlation between PD20FEV1 -AMP and asthma symptom score was analyzed. Values of PD20 FEV1 -AMP were represented as median and quartile range [ M( QR) ] . Results No positive responses to AMP were found in both healthy and URI subjects. On the other hand, positive responses to AMP were found in all the uncontrolled asthmatics ( 100% ) with PD20FEV1 -AMP as 0. 6 mg ( 0. 4 mg) , in 19 partially controlled asthmatics ( 86. 4% ) with PD20 FEV1 -AMP as 5. 38 mg ( 32. 67 mg ) , and in 5 controlled asthmatics( 26. 3% ) with PD20FEV1 -AMP as 40 mg ( 29. 3 mg) . There were negative correlations between the logarithms of PD20 FEV1 -AMP and logarithms of asthma symptom scores ( r = - 0. 598, P lt; 0. 01) . The sensitivity, specificity and accuracy was 72% , 100%, and 84% , respectively. Percentage of subjects who experienced wheezing, cough, dyspnea, swallows stimulation, chest tightness, expectoration and cyanosis during AMP-BPT were 37. 5%, 21. 2%, 15. 4%,7. 7%, 7. 7%, 4. 8%, and 1. 0%, respectively. No severe adverse reaction was found. Conclusions AMP-BPT is helpful to the diagnosis and differential diagnosis of bronchial asthma. It also can be used to evaluate the severity and control level, and to monitor the therapeutic efficacy in clinical practice. Moreover, AMP-BPT is well tolerated with little adverse reaction.