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 effect of myeloid derived suppressor cells ( MDSCs) on airway inflammation of asthmatic mice. Methods Five male BALB/ c mice aged 6 weeks were used for preparing 4T1 tumor bearing mice. Thirty female BALB/ c mice aged six weeks were randomly divided into a normal control group, an athmatic model group, and a cell transplantation group. The MDSCs were separated frommyeloid tissue of tumor-bearing mice using amagnetic cell sorting systemand cultured in RPMI medium 1640 containing GM-CSF. The morphologic characteristics of these cells were observed under lightmicroscope and the phenotypic figures were analyzed with flow cytometry. The mice in the model group and the cell transplantation group were sensitized by ovalbumin and then stimulated with nebulized ovalbumin. The mice in the cell transplantation group were intravenously administered MDSCs which purified by magnetic cell sorting system at 10 days after sensitization. The airway inflammation was evaluated by HE staining. The total and differential cell counts in bronchoalveolar lavage fluid ( BALF) were measured.Results The neutrophil and eosinophil infiltration in pulmonary tissue was dramatically increased in the model group, but not observed in the normal control group and was much milder in the cell transplantation group. The total cell count, the eosinophil and lymphocyte counts in BALF of the model group and the cell transplantation group were significantly higher than those of the normal control group( P lt; 0. 05) , and the number of eosinophils in BALF of the cell transplantation group was decreased when compared with that of the model group( P lt;0. 05) . Conclusion MDSCs via intravenous infusion can effectively suppress airway inflammation in a mouse asthma model.
The number of clinical guidelines developed and published in different countries is increasing worldwide. Too many guidelines do not remain in regular use, even though the aim is to implement them in clinical practice. The scientific validity and reliability of the guidelines need to be reviewed. Here is a case presented to show how to optimally use the evidence-based guideline to improve clinical decision making.
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.
ObjectiveTo investigate the role of acetyl CoA carboxylase (ACC)-induced Th17 development in the pathogenesis of asthma.MethodsA total of 24 C57BL/6 mice were randomly assigned to 4 groups (6 in each group), namely a normal group, an asthma group, a DMSO control group and an ACC inhibitor group. The mice in the asthma group, the DMSO control group and the ACC inhibitor group were sensitized and challenged with ovalbumin (OVA) to establish a model of acute asthma, the mice in the normal group were administrated with equal volume of phosphate buffered saline (PBS). The mice in the ACC inhibitor group were intraperitoneally administrated with TOFA, an ACC inhibitor (dissolved in DMSO firstly, then diluted with PBS solution) twice a week, while the DMSO control group were intraperitoneally administrated with equal concentration of DMSO. All mice were sacrificed 24 days later, then lung tissue and serum were collected. The inflammatory cells infiltrated in lung tissue were assessed by the means of HE staining under light microscope. The total level of IgE in serum was detected by ELISA. The percentage of Th17 cells in CD4+ T cells in lung tissue was evaluated by flow cytometry.ResultsThe inflammatory cells infiltration in the asthma group, the DMSO control group and the ACC inhibitor group increased significantly compared with that of the normal group (3.50±0.14, 3.47±0.08, 2.07±0.20vs. 0.50±0.17, allP<0.001), but there were no significant differences between the DMSO control group group and the asthma group (P>0.05), while administration of TOFA could significantly decrease the inflammatory cells infiltration (P<0.001). The total level of serum IgE in the asthma group, the DMSO control group and the ACC inhibitor group was significantly higher than that in the normal group [(5 680.40±831.40) ng/ml, (5 624.79±365.50) ng/ml, (2 028.95±134.60) g/mlvs. (400.52±57.13) ng/ml, allP<0.008], but there were no significant differences between the DMSO control group and the asthma group (P>0.05), while the total level of serum IgE in the ACC inhibitor group was significantly lower than that in the asthma group (P<0.008). The percentage of Th17 cells in CD4+ T cells in lung tissue increased markedly in the asthma group, the DMSO control group and the ACC inhibitor group compared with the normal group [(2.01±0.12)%, (1.95±0.16)%, (0.82±0.04)%vs. (0.59±0.03)%, bothP<0.008], and also there were no significant differences between the DMSO control group and the asthma group (P>0.05), while administration of TOFA could notably reduce the percentage of Th17 cells (P<0.008).ConclusionInhibition of ACC significantly alleviates the airway inflammation of OVA-induced asthma, and reduces the percentage of Th17 cells in lung tissue and the total level of serum IgE. ACC may participate in the pathogenesis of asthma by inducing Th17 development.
Objective To investigate the effects of diesel exhaust particles ( DEP) on the production of CCL11, CCL24 and CCL26 in asthmatic rats. Methods Fifty SD rats were randomly divided into five groups. Group A was an normal control group. The rats in group B, C, D, and E were sensitized and challenged by ovalbumin ( OVA) to establish asthma model. Then the rats in the group C, D, E were inhaled DEP for 1, 2, 3 weeks, respectively. Lung tissue and brouchoalveolar lavage fluid ( BALF) were collected for detection of CCL11, CCL24, and CCL26 expression by ELISA and q-RT-PCR. Results The transcription of CCL 24, CCL26 gene and the production of CCL24 and CCL26 protein increased significantly compared with the control group ( P lt;0. 05) , and were positively associated with the DEP inhalation time. However, CCL11 gene and protein expression were not changed significantly compared with the control. Conclusion The exposure to DEP can induce the production of CCL24 and CCL26 in the asthmaic rats, which might aggravateairway hyperresponsiveness.
Objective To investigate the association between the -6843G/A polymorphism of highaffinity IgE receptor βchain ( FcεRIβ) gene and asthma susceptibility in Chinese population.Methods We searched Pubmed, EMBASE, CNKI ( Chinese National Knowledge Infrastructure) , Wanfang Datebase, VIP Database up to October 1,2009. Statistical analysis was performed with the software program RevMan 4. 2. 8 and STATA 10. 0. Results A total of 9 case-control studies were included in the meta-analysis. The results indicated that the G allele carriers had a 49% increased risk of asthma in Chinese population ( GG + GA vs. AA: OR=1. 49, 95% CI 1. 01-2. 22) . In the subgroup analysis, the results indicated that the polymorphism was associated with increased risk of asthma in the adults ( GG + GA vs. AA: OR = 1. 83, 95% CI 1. 32- 2. 52) , but not in children ( GG + GA vs. AA: OR = 1. 19, 95% CI 0. 68-2. 08) . Conclusion The -6843G/A polymorphism of FcεRIβ gene is associated with increased asthma susceptibility in Chinese population.
Objective To investigate the expression of RNP(alpha defensins) in guinea pigs with bronchial asthma and the influences of P2Y2 receptors on the expression. Methods Seventy-two adult male guinea pigs were randomly divided into a control group (group A) and an asthma group (group B). The asthma model was established by sensitizing with ovalbumin injection intraperitoneally and challenging with ovalbumin inhalation. Then the A and B groups were divided into following subgroups,ie,the saline groups (A1/B1),ATP groups (A2/B2),and Suramin groups (A3/B3),in which the animals were intervented with saline,ATP,and suramin respectively. Total pulmonary resistance (RL) was measured.Total and differential cell counts in bronchoalveolar lavage fluid (BALF) were measured. Pathological changes of lung were observed under light microscope using HE staining. The plasma levels of RNP and IL-8 were measured by ELISA. The protein and mRNA expressions of RNP and P2Y2 were detected by immunohistochemistry and RT-PCR. Results The RL increased significantly as much as 10% in group B compared with group A. Pathological study revealed that luminal narrowing of bronchus and inflammatory cells infiltration in the asthma group. The total cell and polymorphonuclear neutrophil (PMN) counts in BALF in group B1 were significantly higher than group A1 and B3,but lower than group B2 (Plt;0.05),but no significant difference among group A1,A2,or A3 was found. The RNP expression in plasma and lung tissue in group B1 was higher than group A1 and B3,but lower than group B2 (Plt;0.05). The RNP expression in plasma and lung tissue was lower in group A1 than group A2,but higher than group A3(Plt;0.05). The IL-8 expression in plasma in group B1 was significantly higher than group A and B3,but lower than group B2 (Plt;0.05) but no significant difference among group A1,A2,or A3 was found(Pgt;0.05). RNP protein expressed predominantly in lung tissues,especially where the PMN infiltrated. The expression of RNP mRNA were consistent with the RNP protein expression in all groups. P2Y2 mRNA expression in group A1 was lower than group A2,and higher than group A3 (Plt;0.05).P2Y2 mRNA expression in group B1 was lower than group B2 but higher than group B3 (Plt;0.05). The linear correlation analysis showed that RNP had no significant correlation with PMN and IL-8 in group A,and was positively correlated with P2Y2 mRNA (Plt;0.05) while RNP was positively correlated with PMN,IL-8,and P2Y2 mRNA in group B. Conclusion RNP expression increases in bronchial asthma guinea pigs and may be related to P2Y2 receptors.
Objective To investigate the percentage of CD4 + CD25 + Treg cells and expression of Foxp3 mRNA in asthmatic patients and the impacts of inhaled steroids.Methods The percentages of CD4 +CD25 + Treg cells was assayed by flow cytometry and the expression of Foxp3 mRNA was detected by RT-PCR in peripheral blood mononuclear cells from the patients with chronic persistent asthma before and after steroids inhalation in comparison with healthy control. The forced expired volumin one second/predicted value( FEV1% pred) and peak expired flow( PEF) were measured by spirometry. Results The level of CD4 + CD25 + Treg cells and the expression of Foxp3 mRNA were lower in asthmatics before steroids treatment than those in control ( P lt; 0. 05) which were increased significantly after steroids treatment ( P lt; 0. 05) .FEV1% pred and PEF were declined significantly than those in control but improved markedly after treatment ( P lt; 0. 05) . Conclusions The insufficiency of amount and function of immue-suppressive CD4 + CD25 +Treg cells may play a role in the pathogenesis of asthma. Inhaled steroids can improve the lung function of asthmatics by upregulating the level of CD4 + CD25 + Treg and Foxp3.