信号转导及转录激活因子3对心肌细胞基质金属蛋白酶-10活性的影响

摘要

Objective: To investigate the effect of signal transducer and activator of transcription3 ( STAB) on up-regulation ofmatrix metalloproteinase-10( MMP40) activity induced byC-reactlve protein( CRP) in neonatal rat cardhnyocytesMethods:W e studied the neonatal rat cardionyocytes with elevated MMP40 level which was induced by CRP Phospho-specific antibody forSTAB was used to detemine the egression ofSTAB by W estem blot analysis Cardhnyocytes nuclearpre-tehwas extracted for filter assay to monitor STAT3 DNA binding activity inMMP40 promoter The cells were further transfected with snail inferehg RNA( siE^NA) of STAT3 to observe the role of STAT3 in up-regulation ofMMP40 activity induced by CRP.Results: The phosphorylated STAT3 level hcreased5 minutes after CRP trearnent and lasted for2 hours, while the total STAT3 level renained the same NuclearSTATi DNA-binding activitywas significantly increased afterCRP treatnentatdifferent tine points, and themaxmal level was obtained atl2 hours,P<0. 01. W ith STAT3 sHNA transfectbn, MMP40 activitywas significantly inhrbited,P <0. 01, SIAT3 protein expression and DNA binding activity were also inhibitedConclusion: SIAT3 canmediate up- regulation of CRP-induced MMP40 activity in neonatal rat cardiomyocytes%目的:探讨信号转导及转录激活因子3(STAT3)对心肌细胞基质金属蛋白酶-10(MMP-10)活性的影响.方法:以炎症细胞因子C反应蛋白(CRP)诱导基质金属蛋白酶-10上调的原代乳鼠心肌细胞为研究对象.使用STAT3的特异磷酸化抗体,用蛋白免疫印迹杂交技术检查STAT3的磷酸化水平.提取细胞核蛋白,应用滤板法检测核内转录因子STAT3的脱氧核糖核酸(DNA)结合活性,并转染STAT3小分子干扰核糖核酸(siRNA),进一步分析转录因子STAT3对基质金属蛋白酶-10的调节作用.结果:磷酸化的STAT3在C反应蛋白刺激后5 min即可出现高表达,一直持续至2 h,而总的STAT3不随C反应蛋白作用的时间而改变.C反应蛋白作用不同时间,核内STAT3的DNA结合活性均可明显增加,且在12 h达到高峰 (P<0.01).加入STAT3 siRNA后,基质金属蛋白酶-10的活性明显减弱(P<0.01),STAT3的蛋白表达以及核内STAT3的DNA结合活性(P<0.01)也均降低.结论:STAT3作为转录因子能够促进C反应蛋白诱导基质金属蛋白酶-10活性的增加.