PPARα和TGF-β_1调控糜酶促进乳鼠心肌纤维化的信号转导机制研究  

Signal Transduction Mechanism of Myocardial Fibrosis through PPARα and TGF-β_1 Induced by Chymase in Neonatal Rat

作　　者：赵晓燕[1] 苏金林[2] ZHAO Xiaoyan;SU Jinlin(Department of Cardiology,the Fifth Hospital of PLA,Yinchuan 750004;Department of CardiothoracicSurgery,the General Hospital of Ningxia Medical University,Yinchuan 750004)

机构地区：[1]解放军第五医院心内科,银川750004 [2]宁夏医科大学总医院心胸外科,银川750004

出　　处：《宁夏医科大学学报》2018年第4期418-423,共6页Journal of Ningxia Medical University

基　　金：全军医药卫生科研基金资助课题(914031)

摘　　要：目的探讨肥大细胞糜酶促进乳鼠心肌纤维化的主要细胞内信号转导作用机制。方法采用胰酶消化法分离、培养SD乳鼠的心肌成纤维细胞(CFs),分为对照组、不同浓度糜酶组、糜酶抑制剂(CHI)预处理组和CHI单独作用组。以酶联免疫吸附法(ELISA)测定CFs培养上清Ⅰ、Ⅲ型胶原蛋白含量,逆转录聚合酶链式反应(RT-PCR)检测过氧化物酶体增殖物激活受体α(PPARα)和转化生长因子-β_1(TGF-β_1)m RNA表达水平,蛋白免疫印迹法(Western blot)检测PPARα和TGF-β_1的蛋白表达水平。结果 CFs培养上清Ⅰ、Ⅲ型胶原蛋白含量随糜酶浓度的增加而增加,15、30和60μg·L^(-1)糜酶组Ⅰ、Ⅲ型胶原蛋白均较对照组升高(P<0.05或<0.01)。糜酶以浓度依赖方式减少CFs的PPARαm RNA和蛋白表达、增加TGF-β_1m RNA和蛋白表达,15、30和60μg·L^(-1)糜酶组与对照组相比差异均有统计学意义(P<0.05或<0.01)。10μmol·L^(-1) CHI可完全阻断30μg·L^(-1)糜酶诱导的Ⅰ、Ⅲ型胶原合成,并使PPARαm RNA和蛋白表达增加、TGF-β_1m RNA和蛋白表达减少。结论肥大细胞糜酶可促进乳鼠心肌纤维化,其细胞内信号转导机制与PPARαm RNA和蛋白表达下调、TGF-β_1m RNA和蛋白表达上调有关。Objective To investig ate the intracel lular signal transduction of myocardial fibrosis induced by mast cell chymase in neonatal rat. Methods Cultured cardiac fibroblasts（CFs）of neonatal SD rats were isolated by trypsinization. They were devided into control group,different concentration chymase groups,pretrentment with chymase inhibitor（CHI）group and CHI group. The Type Ⅰ and Type Ⅲ collagen contents in cultured supernatants of CFs were evaluated by ELISA. The m RNA expressions of peroxisome proliferator-activated receptor α（PPARα）and transforming growth factor-β1（TGF-β1） in CFs were determined by RT-PCR. Western blot was used to measure the protein expressions of PPARα and TGF-β1.Results 15,30 and 60μg·L-1 chymase remarkably increased Type Ⅰ and Type Ⅲ collagen,respectively,both in a concentration-dependent manner compared with those of the controls（P〈0.05 or 〈0.01）. Chymase obviously decreased the PPARα,increased the TGF-β1 m RNA and protein expressions,in a dose-dependent manner. The PPARα,TGF-β1 m RNA and protein stimulated by 15,30 and 60μg·L-1 chymase were significantly different from those of the controls（P〈0.05 or 〈0.01）. Tratment with CHI could completely block the synthesis of type I and Ⅲ collagen induced by 30μg·L-1 chymase,and increase the expression of PPARαm RNA and protein,and decrease the expression of TGF-β1 m RNA and protein. Conclusions Mast cell chymase can induce myocardial fibrosis in neonatal rat. The intracellular signal transduction is associated with the downregulation of PPARα and upregulation of TGF-β1 m RNA and protein.

关 键 词：糜酶 心肌纤维化 信号转导 过氧化物酶体增殖物激活受体Α 转化生长因子-β1 

分 类 号：R542.23[医药卫生—心血管疾病]