哮喘大鼠血单个核细胞中STAT5b mRNA和IL-4 mRNA的表达及布地奈德的影响

The expression of STAT5b mRNA and IL-4 mRNA of mononuclearcell in blood of a rat model of asthma and the modulatory effect of budesonide

目的研究哮喘大鼠血单个核细胞中信号转导和转录激活因子STAT5bmRNA和IL-4mRNA的转录表达及布地奈德(BUD)对其表达的影响。方法30只体重为140￣200g清洁级SD雌性大鼠,随机分为3组:哮喘组(A组)、BUD组(B组)、正常对照组(C组)。对血中嗜酸性粒细胞(EOS)计数;应用双抗体夹心ELISA测定血浆中IL-4和IFN-γ水平;采用SYBRGREENI荧光定量PCR法测定STAT5bmRNA和IL-4mRNA的相对含量。结果(1)A组血中单个核细胞STAT5bmRNA和IL-4mRNA的表达均高于B组和C组(P<0.01);B组与C组之间差异无统计学意义(P>0.05)(。2)STAT5bmRNA与IL-4mRNA的表达呈正相关(P<0.01),且两者的表达分别与血浆中的IL-4水平、EOS绝对值呈正相关(P<0.01),与血浆中IFN-γ水平呈负相关(P<0.01)。结论哮喘大鼠血中单个核细胞STAT5bmRNA和IL-4mRNA的表达增强且呈正相关;布地奈德可以下调STAT5bmRNA和IL-4mR-NA的表达,可能是其抑制哮喘气道炎症形成的重要机制之一。

Objective To study the expression of signal transducer and activator of transcription 5b mRNA and interleukin-4 mRNA of mononuclearcell in blood of a rat model of asthma and the modulatory effect of budesonide（BUD）. Methods Thirty female SD rats were randomly divided into three groups ： asthma group, BUD group and the control group. In the experiment, the rat model of asthma was established by ovalbumin （OVA） sensitization method. The rats in each group were sacrificed 24 h after the last sensitization. The eosinophils （EOS） count in biood was performed. The concentrations of IL-4 and interferon- γ （IFN- γ ）in plasma were measured by using sandwich ELISA. The relative content of STAT5b mRNA and IL-4 mRNA were detocted with SYBR GREEN 1 fluorescent quantitation PCR method. Results （1）The relatively expressive content of STAT5b mRNA and IL-4 mRNA of mononuclearcell in blood of a rat model of asthma was significantly higher than that of the BUD group （P〈0.01） and the control group （P〈0.01）. （2）There was a positive correlation between the expressive content of STATSb mRNA and IL-4 mRNA （P〈0.01）. （3）The absolute count of EOS in blood and the concentration of IL-4 in plasma of the asthma group were all significantly higher than those of the BUD group and the control group （P〈0.01）. The concentration of IFN-γ in plasma of the asthma group was significantly lower than that of the BUD group and the control group （P〈0.01）. （4）The expression of STAT5b mRNA and IL-4 mRNA correlated positively with the conncentration of IL-4 and the absolute count of EOS ,respectively （P〈0.01）. The expression of STAT5b mRNA and IL-4 mRNA correlated negatively with the concentration of IFN-γ ,respectively. Conclusion STAT5b mRNA and IL-4 mRNA of mononuclear cell were found strongly expressed in the blood of the rat asthma models, and showed a positive correlation between them. Budesonide had an inhibitory effect on expression of STAT5b mRNA and IL-4 mRNA. It significantly depressed the expression of STAT5b mRNA and IL-4 mRNA, Which may be a key process in modulatory mechanism of asthma.