摘要
目的研究布地奈德(BUD)对支气管哮喘大鼠支气管信号转导子和转录激活子6(STAT6)基因和蛋白表达的调控作用。方法30只清洁级幼年雄性SD大鼠随机分为对照组(A组)、哮喘组(B组)和BUD组。对支气管肺泡灌洗液(BALF)进行细胞总数、嗜酸性粒细胞(EOS)计数和分类计数;应用双抗体夹心酶联免疫吸附试验法测定BALF中IL-4、IL-12浓度;采用免疫组化法和原位杂交法分别检测STAT6蛋白和STAT6mRNA表达的变化。结果(1)B组BALF中细胞总数、EOS绝对值和EOS占细胞总数的百分比(EOS%)均显著高于A组(P<0.01),BUD组BALF中上述各项指标较B组均显著降低(P<0.01);(2)BALF中IL-4的浓度B组显著高于A组(P<0.01),BUD组较B组显著降低(P<0.01),而IL-12的浓度B组显著低于A组(P<0.01),BUD组较B组显著升高(P<0.01);(3)B组支气管上皮细胞STAT6蛋白和STAT6mRNA阳性表达较A组明显增强(均为P<0.01),BUD组较B组明显减弱(均为P<0.01);(4)支气管上皮细胞STAT6蛋白、STAT6mRNA分别与BALF中的IL-4浓度呈显著正相关,与BALF中EOS绝对值呈显著正相关;而与IL-12浓度呈显著负相关。结论哮喘大鼠支气管STAT6及其mRNA较强表达,上皮细胞是其主要表达细胞;BUD有抑制气道炎症的作用,下调STAT6及其基因表达,使IL-4合成减少可能为其重要作用机制。
Objective To study the modulation of budesonide（BUD） on signal transducer and activator of transcription 6 （STAT6） and its gene expression in the rat model of asthma. Methods Thirty male SD rats were randomly divided into three groups： the control group（group A）, asthma group（group B） and budesonide group（BUD group）, animals in each group were killed 24 h after the last challenge. In the experiment, the rat model of asthma was established by the ovalbumin（OVA） challenge methods. The lung tissue was gained from the left lung, bronchoalvcolar lavage fluid（BALF） was gained from the right lung. The total cell numbers, eosinophils （EOS） numbers and differentiated cell numbers in BALF were counted by different count fluids; the concentration of IL-4 and IL-12 in BALF was measured by sandwich ELISA; the protein expressions of STAT6 were detected by immunohistochemistry techniques; the mRNA expressions of STAT6 were determined by hybridization in situ. Results （ 1 ） The total cell numbers in BALF, the absolute numbers of EOS, the ratios of eosinophils to the total cell numbers（EOS% ） of asthma group were all significantly higher than those of the control group（ P 〈 0.01） ; the total cell numbers in BALF, the absolute numbers of EOS, EOS% of budesonide group were all significantly lower than those of asthma group （ P 〈 0.01）. （2） The concentration of IL-4 in BALF of asthma group was significantly higher than that of control group（ P 〈 0.01）, the concentration of IL-4 of budesonide group was significantly lower than that of asthma group; while the concentration of IL-12 in BALF of asthma group was significantly lower than that of control group（ P 〈 0.01）, the concentration of IL-12 of budesonide group was significantly higher than that of asthma group. （3） Immunohistochemistry and hybridizationin situ showed that the content of protein and mRNA expressions of STAT6 around the bronchus of asthma group were all significantly higher than those of the control group （ P 〈 0.01 ） , while those of budesonide group were significantly lower than those of the asthma group , the epithelial cells were the chief expression cells. （4） Them was a significant positive correlation between the concentration of IL-4 in BALF, the content of STAT6 and STAT6 mRNA respectively in the bronchial epithelial cells; them was a significant correlation between the absolute numbers of EOS in BALF, the content of STAT6 and STAT6 mRNA respectively in the epithelial cells; them was also a significant negative correlation between the concentration of IL-12 in BALF, the content of STAT6 and STAT6 mRNA respectively. Conclusion Budesonide had an inhibitory effect on airway inflammation, it significantly depressed STAT6 and its mRNA expression, thus reduced the synthesis of IL-4 may be key in modulating mechanism of asthma.
出处
《中华微生物学和免疫学杂志》
CAS
CSCD
北大核心
2005年第7期588-593,共6页
Chinese Journal of Microbiology and Immunology
基金
浙江省自然科学基金资助项目(No.301485)
