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.
ObjectiveTo investigate the expression of programmed cell death-1 (PD-1), interferon-γ (IFN-γ), interleukin-4 (IL-4) and T help cells (Th) in peripheral blood of patients with asthma.MethodsForty-one asthma patients were divided into an acute group (20 cases) and a chronic group (21 cases) according to the disease state of asthma. Another 18 healthy subjects were recruited as a control group. Peripheral blood samples were collected from all the subjects at admission or inclusion. The concentrations of PD-1, IFN-γ and IL-4 were detected by enzyme-linked immunoassay method. The expressions of Th1 and Th2 were detected by flow cytometry method.ResultsThe PD-1 and IFN-γ concentrations, Th1 proportion and Th1/Th2 ratio in the two asthma groups were reduced compared with the healthy control group, and were significantly lower in the acute group compared with the chronic group (all P<0.05). The IL-4 level and Th2 proportion in the two asthma groups were increased compared with the healthy control group, and were significantly higher in the acute group than the chronic group (allP<0.05). In the acute group, the PD-1 level was positively correlated with IFN-γ and Th1 level (r values were 0.678 and 0.712, respectively), and negatively correlated with IL-4 and Th2 (r values were –0.745 and –0.700, respectively).ConclusionThe concentration of PD-1 in patients with asthma is reduced especially in acute asthma, and shows close correlation with conventional index of asthma.
Objective To establish a beta 2 adrenergic receptor ( β2 R) down-regulative asthmatic model, to explore the mechanism of β2 R down-regulation and effectiveness of corticosteroids. Methods Thirty-two BALB/c mice were divided into four groups, ie. a control group, an asthmatic group, a β2R downregulative group, and a dexamethasone group. The asthmatic group, the β2 R down-regulative group and the dexamethasone group were sensitized on 0th, 14th and 21th day by intraperitoneal injection of ovalbumin ( OVA) together with aluminumhydroxide in a total volume of 200 μL. Fromthe 28th day on, the mice were challenged with an aerosol of 1% OVA( W/V) in saline using an ultrasonic nebulizer 30 min/d for a week.The β2 R down-regulative group and the dexamethasone group underwent the same procedure as the asthmatic group besides daily intraperitoneal injection of 60 μg salbutamol and inhaling an aerosol of 0. 01%salbutamol 30 min/d for a week half an hour before challenged with OVA. The dexamethasone group was injected dexamethasone 5 mg·kg- 1·d - 1 for a week by intraperitoneal injection on the basis of OVA challenge and salbutamol intervention. The control group was sensitized and challenged with PBS. Airway resistance was measured by plethysmography. IL-4 and IFN-γlevels in BALF, and total IgE concentration in serum were measured by ELISA. Total and differential cell counts in bronchial alveolar lavage fluid ( BALF)were measured. Total amount and number of β2 R in lung tissue were evaluated by immune blotting analysis and radioligand receptor binding assay, respectively. Results Compared to the control group and the dexamethasone group, airway resistance of the asthmatic group and the β2 R down-regulative group increasedobviously provocated by a high dose of acetylcholine ( P lt;0. 01) . Eosinophil, neutrophil, lymphocyte counts in BALF, IL-4 level in BALF, and total IgE in serumincreased significantly also ( P lt;0. 01) , while IFN-γin BALF decreased significantly. Compared to the control group, the asthmatic group and the dexamethasonegroup, the total amount and number of β2 R significantly decreased in the β2 R down-regulative group ( P lt;0. 01) , while no significant difference was found among the control group, the asthmatic group and the dexamethasone group. Conclusions β2 R down-regulative asthmatic model can be successfully establishedby peritoneal injection and inhalation of salbutamol on the basis of OVA sensitization and challenge.Dexamethasone can prevent the down-regulation of β2 R.
Objective To explore the possible anti-inflammatory mechanism of peroxisome proliferators-activated receptor（PPAR） gamma-agonists by investigating the effects of Rosiglitazone on the expression of phosphorylation of signal transducer and activator of transcription 6（p-STAT6） and the secretion of interleukin（IL）-4 in T-lymphocytes from patients with acute asthma.Methods Peripheral blood T-lymphocytes from 10 healthy volunteers（group A） and 10 patients with acute asthma were isolated，purificated and cultured.T-lymphocytes from the asthma patients were divided into a control group（group B） and a Rosiglitazone treated group（group C）.Rosiglitazone was added with a single dose of 10-4 mol/L at 0 hour of cultrue.After cultured for 48 hours，the concentration of IL-4 in supernatant of each groups were detected by ELISA.The express of p-STAT6 in the T-lymphocytes were determined by Western blot and immunohistochemical techniques.Results The levels of IL-4 were increased markedly in group B than those in group A and group C[（170.34±9.05）pg/mL vs（76.82±7.06）pg/mL and（123.59±8.70）pg/mL，both Plt;0.01]，and which in group C was significantly lower than group A（Plt;0.01）.The levels of p-STAT6 in T lymphocytes were increased markedly in group B than in group A and C[Western blot：（6.28±0.19 vs 3.07±0.18 and 4.12±0.16；immunohistochemistry：（36.58%±7.41）% vs（11.39±4.02）% and（23.92±5.8）%，all Plt;0.01），and which in group C were significantly higher than that in group B（both Plt;0.01）.There was a positive correlation between the level of p-STAT6 and IL-4（Plt;0.01）.Conclusion The levels of p-STAT6 and IL-4 in T-lymphocytes of patients with acute asthma were suppressed by Rosiglitazone in vitro.
ObjectiveTo explore the application of pulmonary ventilation and perfusion imaging (V/P SPECT/CT) in quantitative evaluation of ventilation and perfusion function and its potential value in guiding local treatment of lung in patients with asthma.MethodsA total of 20 patients with asthma were included in this study. All patients underwent V/P SPECT/CT and pulmonary function test, and symptoms were assessed by the ACT questionnaire. Patients were graded for degree of airway obstruction according to V/ P SPECT/CT image visual scoring criteria. The comprehensive lung function (%) of the patients was quantitatively evaluated by combining the ventilation and perfusion defect of each lung segment in V/P imaging. The correlation between the degree of airway obstruction, comprehensive lung function, pulmonary function test and ACT score was analyzed.ResultsV/P SPECT/CT imaging can be used to grade the degree of airway obstruction in asthma patients (0-3 grade). Airway obstruction grading by V/P SPECT/CT visual score was associated with predictive forced expiratory volume in one second (FEV1%pred) of patients (r=–0.74, P<0.001). V/P SPECT/CT can also comprehensively evaluate ventilation and perfusion function in patients with asthma, and comprehensive lung function measured by this method was also correlated with FEV1%pred (r=0.629, P=0.003). V/P SPECT/CT can be used to quantitatively analyze the percentage of ventilation and perfusion function in each lung lobe. Compared with V/P SPECT/CT results, the CT volume overestimates the contribution in the upper lobes, and underestimates the lower lobes contribution to overall function.ConclusionsV/P SPECT/CT can be used as a new method to directly reflect the degree of airway obstruction in patients with asthma. Moreover, it can comprehensively and quantitatively evaluate the ventilation and perfusion function of asthma patients. V/P SPECT/CT can also be used to evaluate lobe function in patients with asthma, helping to identify the heterogeneity of changes in pulmonary function in patients with asthma, and has potential value for future treatment targeting specific areas of the lung.
ObjectiveTo determine whether there is an imbalance of KLF2/RelA in peripheral blood neutrophils in patients with bronchial asthma, and explore the relationship between KLF2/RelA imbalance and neutrophil apoptosis.MethodsFrom April 2011 to April 2012, a total of 39 patients with acute attack of asthma in Hunan People's Hospital and Third People's Hospital of Changsha were enrolled, with 13 cases in mild asthma group, 17 cases in moderate asthma group, and 9 cases in severe asthma group. Fifteen healthy subjects were recruited as control group. Peripheral blood were collected from all subjects followed by separation of neutrophils. The apoptosis of neutrophils were measured by flow cytometry. The expression of KLF2 and RelA were detected by Western blot. The relationship between the ratio of KLF2/RelA and neutrophil apoptosis rate was analyzed by Pearson correlation test.ResultsNeutrophil apoptosis rates in the mild, moderate and severe asthma groups [(4.45±0.76)%, (2.10±0.25)%, (1.81±0.67)%, repectively] were lower than that in the healthy control group [(5.36±0.57)%, all P<0.01]. The apoptosis rates of neutrophils in the moderate and severe asthma groups were lower than that in the mild asthma group (bothP<0.01), but there was no significant difference between the moderate asthma group and the severe asthma group (P>0.05). The ratios of neutrophil KLF2/RelA in the mild, moderate and severe asthma groups were lower than that in the normal control group (0.667±0.351, 0.384±0.203, 0.536±0.293vs. 4.038±2.011, all P<0.01). There was no significant difference between the groups of mild, moderate and severe asthma (P>0.05). The neutrophil apoptosis rate was positively correlated with the percentage of neutrophil KLF2/RelA (r=0.592 0, P<0.000 1).ConclusionThere is an imbalance of KLF2/RelA in peripheral blood neutrophils in patients with bronchial asthma, and the imbalance of KLF2/RelA may be the mechanism of apoptosis of peripheral blood neutrophils.
Objective To examine the expression of promoter CpG island methylation of Notch1 gene and explore the variable sites for DNA methylation in lung CD4 + T cells of asthmatic rat models.Methods An ovalbumin ( OVA) sensitized- challenged asthmatic rat model was established. Total T cells were isolated and CD4 + T lymphocytes were purified using magnetic beads. Twenty Wistar rats were randomly divided into a control group and an asthma group ( n = 10 in each group) . CD4 + T cells were isolated by immunomagnetic beads and identified by flow cytometry ( FCM) . Realtime PCR was employed to examine the mRNA expression of Notch1 gene in lung CD4 + T cells and the methylation level of Notch1 gene was examined by methylation-specific PCR. Results The mRNA expression of Notch1 in lung CD4 + T cells of the asthma group was 2. 254 ±0. 403 times as much as that of the control group. The total methylation level of asthma group was lower than that of the control group ( 0. 150 ±0. 108 vs. 0. 300 ±0. 667, P lt;0. 01) . Conclusion Promoter demethylation is one of the major mechanisms of Notch1 gene up-regulation in pathogenesis of asthma.
Objective To measure the serum level of adiponectin and explore its clinical implication in patients with asthma in acute exacerbation and remission phase. Methods 97 patients with asthma were recruited, including 50 patients with asthma in acute exacerbation and 47 patients in remission phase fromOctober 2010 to September 2011. 27 healthy nonsmoking volunteers of normal weight ( BMI range of 18.5-24. 9 kg/m2 ) were included as control. The concentrations of adiponectin and tumor necrosis factor alpha ( TNF-α) in serum were measured by enzyme-linked immunosorbent assay ( ELISA) . The lung function was tested in all subjects. The correlations between adiponectin, TNF-αand lung function were investigated. The data was analyzed using SPSS 19. 0 software. Variables were compared with one-way ANOVA. The correlations between variables were analyzed using Peason’s correlation coefficient or Spearman correlation coefficient.Results Serum adiponectin level was significantly lower in the patients with asthma in acute exacerbation [ ( 246 ±1. 21) ng/mL] than that in the healthy subjects [ ( 9. 64 ±4. 88)ng/mL] and the patients in remission phase [ ( 3. 79 ±0. 96) ng/mL] ( P lt; 0. 01) , while serum adiponectin level was also significantly lower in the patients in asthma remission phase than that in the healthy subjects ( P lt; 0. 01) . The serum adiponectin level in the patients with asthma in acute exacerbation or in asthma remission phase was negatively correlated with the serum TNF-α level ( P lt; 0. 01) , and was positively correlated with FEV1 /predicted value ( P lt; 0. 01) . Conclusions The serum adiponectin is reduced in asthma patients and may play a protective role in asthma.
ObjectiveTo evaluate the prevalence of obstructive sleep apnea hypopnea syndrome (OSAHS) in patients with asthma, and explore the association of OSAHS with asthma. MethodsPatients who were diagnosed as asthma between March 2014 and February 2015 were recruited in the study. They were categorized into an OSAHS group and a non-OSAHS group according to the Berlin questionnaire. The data of clinical characteristics and pulmonary function test were collected. Logistic regression analysis was performed to evaluate the factors associated with the incidence of OSAHS in asthma. ResultsA total of 64 patients with asthma were enrolled and 36 patients were complicated with OSAHS. The body mass index (BMI), allergic rhinitis history, inspiratory capacity, maximal mid-expiratory flow and provoking dose which make FEV1 reduce 20% were significantly different between two groups (all P < 0.05). Multivariate logistic regression analysis revealed that the increased BMI was an independent risk factor of OSAHS in patients with asthma. ConclusionThe occurrence of OSAHS with asthma is very high, and BMI may be an important associated risk factor.
Objective To explore the influencing factors of inhalation medication compliance in Chinese asthma patients, and to provide evidence for improving the compliance of patients with inhalation therapy. Methods PubMed, China National Knowledge Infrastructure, Wanfang, Chongqing VIP, and SinoMed were searched for literature on factors influencing inhalation medication compliance in Chinese asthma patients from the establishment of databases to December 2021. Meta-analysis was performed using RevMan 5.2 software. Results A total of 16 studies were included, with a sample size of 2 600 cases, 1 084 cases of good compliance with inhalation administration, 1 516 cases of poor compliance with inhalation administration, and good compliance with inhalation administration accounted for 41.69%. The literature quality evaluation scores were all ≥4 points, all of which were of medium quality and above. Meta-analysis showed that the factors affecting inhalation compliance of asthma patients included age [odds ratio (OR)=0.54, 95% confidence interval (CI) (0.32, 0.91), P=0.02], educational level [OR=0.57, 95%CI (0.36, 0.90), P=0.02], doctor-patient relationship [OR=0.42, 95%CI (0.19, 0.93), P=0.03], disease severity [OR=0.25, 95%CI (0.11, 0.58), P=0.001], degree of mastery of asthma knowledge [OR=2.51, 95%CI (1.11, 5.65), P=0.03], degree of mastery of inhalation technique [OR=8.66, 95%CI (3.20, 23.40), P<0.0001], adverse drug reaction [OR=0.23, 95%CI (0.13, 0.41), P<0.00001]. Conclusion The compliance of inhaled dosing in Chinese asthma patients needs to be improved urgently. Age, education level, doctor-patient relationship, disease severity, mastery of asthma knowledge, mastery of inhalation technology, and adverse drug reactions are the important influencing factors of inhaled medication compliance.