热休克蛋白70调节突触融合蛋白Syntaxin 1在哮喘中的表达

The modulation of heat shock protein 70 on the expresson of syntaxin1 in asthmatic model

目的探讨热休克蛋白70(heat shock protein 70,HSP70)对突触融合蛋白Syntaxin1(SYX1)在哮喘大鼠肺组织中表达水平的调节及相互作用。方法 30只健康Wistar大鼠按随机原则分为对照组、哮喘组、哮喘+地塞米松组,每组10只。通过卵清蛋白(ovalbumin,OVA)致敏、激发建立哮喘大鼠模型,采用免疫组织化学、逆转录PCR及蛋白免疫印迹检测3组间HSP70及SYX1基因和蛋白表达水平,免疫共沉淀技术检测HSP70与SYX1的相互关系。结果与对照组比较,哮喘组HSP70及SYX1基因和蛋白表达水平均增加,差异有统计学意义(P<0.05,P<0.05);与哮喘组比较,哮喘组+地塞米松组HSP70及SYX1基因与蛋白表达水平均降低,差异有统计学意义(P<0.05,P<0.05),但与正常对照组比较,差异均无统计学意义(P>0.05,P>0.05)。免疫共沉淀结果显示在哮喘大鼠肺组织中HSP70与SYX1存在相互作用。结论 HSP70及SYX1在哮喘肺组织中表达水平均明显增高,HSP70通过调节SYX1表达水平及相互作用共同参与哮喘的发病机制,且其表达受地塞米松的抑制,为临床寻找药物干预新的靶点提供了理论依据。

Aim To investigate the relationship between heat shock protein 70（HSP70） and syntaxin1（SYX1） in bronchopulmonary tissues in asthmatic rat model and its clinical significances.Methods Thirty adult Wister rats were randomly divided into three groups： control group（n = 10）,asthma group（n = 10） and a group of asthma treated with dexamethasone（DXM group,n = 10）.Asthma rat model was established by sensitization and stimulation with ovalbumin（OVA） conjuncted with Al（OH） 3.Immunohistochemistry,Western blot,Reverse transcription PCR（RT-PCR） were used to evaluate the expression of HSP70 and SYX1 in bronchopulmonary tissue in these groups.Co-immunoprecipitation（CO-IP） assay was used to identify the interaction of HSP70 and SYX1.Results The overexpression of HSP70 and SYX1 at gene and protein levels were increased significantly in asthma group（P 0.05,P 0.05） compared to the control group.The expression of HSP70 and SYX1 was significantly reduced in DXM group compared with asthma group（P 0.05,P 0.05）.However,there was no significant difference between DXM group and control group（P 0.05,P 0.05）.CO-IP indicated that there was an interaction between SYX1 and HSP70.Conclusions The upregulation of HSP70 and SYX1 is detected in asthmatic bronchopulmonary tissues and there is a modulation of HSP70 on presynaptic protein,SYX1,which may be involved in the pathogenesis of asthma,and their expression levels are negatively regulated by dexamethasone.