骨髓间充质干细胞治疗增加心脏梗死区肌纤维母细胞聚集的观察  

Mesenchymal stem cells implantation increases the myofibroblasts congregating in infarct region in arat model of myocardial infarction

作　　者：杜优优[1] 姚瑞[1] 蒲实[1] 赵晓燕[1] 刘光辉[1] 赵洛沙[1] 陈庆华[1] 李凌[1] 

机构地区：[1]郑州大学第一附属医院心内科,450052

出　　处：《中华心血管病杂志》2012年第12期1045-1050,共6页Chinese Journal of Cardiology

摘　　要：目的探讨骨髓间充质干细胞（MSC）对梗死心肌中肌纤维母细胞聚集的调节作用。方法采用结扎大鼠冠状动脉前降支的方法复制心肌梗死（MI）模型，实验动物应用随机数字表进行完全随机化分组，分为假手术组（仅穿线不结扎冠状动脉，n=8）、心肌梗死＋磷酸盐缓冲液（MI＋PBS）组（结扎冠状动脉＋心肌注射PBS溶液，n=8）和MI＋MSC组（结扎冠状动脉＋心肌注射MSC，n=8）。通过心脏超声检查、血液动力学检查和Masson三色染色等方法分别检测左心室射血分数（LVEF）、短轴缩短率（Fs）、左心室收缩末压力（LVSP）、左心室舒张末压力（LVEDP）、左心室压最大升降速率（±dp／dtmax）、MI面积、梗死区室壁厚度和心脏质量／体质量等指标，评价MSC对大鼠心脏功能及心室重构的影响。分别采用荧光免疫组化染色、实时定量逆转录PCR、Westernblot等方法检测肌纤维母细胞向梗死区聚集、移植MSC存活和分化、转化生长因子p，（TGF—β，）-Smad2信号通路激活等情况。结果（1）心室重构和心脏功能指标检测结果：术后28d，与MI＋PBS组比较，MI＋MSC组的心脏质量／体质量[（3．04±0．16）mg／g比（3．34±n14）mg／g，P〈Q01]及心脏梗死面积[（38．72±2．38）％比（46．36±2．81）％，P〈0．01]较低；梗死区室壁厚度较大[（0．93±0．17）mm比（0．65±0．16）mm，P=0．01]；LVEF[（32．5±5．9）％比（26．5±4．5）％，P=0．03]及Fs[（30．4±3．3）％比（24．8±4．2）％，P〈0．01]较高；改善血液动力学参数，LVSP较高（P=0．01），LVEDP较低（P〈0．01）。（2）与MI＋PBS组比较，MI＋MSC组大鼠心脏梗死区肌纤维母细胞聚集数量较高[（196±20）／mm2比（89±25）／mm2，P〈0．01]，其中部分绿色荧光蛋白（GFP）＋移植细胞同时表达d—SMA＋。（3）与注射PBS比较，移植MSC可以明显增加梗死区TGF—p，mRObjective To investigate the modulation effects of mesenchymal stem cells （MSC） implantation on the myofibroblasts congregating in the infarct region after myocardial infarction （MI）. Methods MI was induced in SD rats by left anterior descending coronary artery ligation, and the experimental animals were assigned randomly into the sham group, MI ± PBS group and MI ± MSC group （myocardial injection of 0. 1 ml 2 x 107/ml in four locations in the infarct region）. Echocardiography, hemodynamic examinations and Masson trichrome staining were performed. Implanted MSC differentiation and myofibroblasts congregating in infarct region were investigated by immunofluorescence staining. TGF-β1- Smad2 signaling pathway was examined by real-time RT-PCR and Western blot. Results （ 1 ） Four weeks late, heart-weight/body-weight ratio [ （ 3.04 ± O. 16 ） mg/g vs. （ 3.34 ± 0. 14） mg/g, P 〈 0. 01 ] and myocardial infarction size [ （38.72 ± 2. 38） % vs. （46.36 ± 2. 81 ） %, P 〈 0. 01 ] were significantly reduced in MI ＋ MSC group than in MI ＋ PBS group, while scar thickness of infarct region was thicker [ （0. 93 ±0. 17）mmvs. （0.65±0.16） mm, /9=0.01], and LVEFwas higher [LVEF： （32.5 ±5.9）% vs. （26.5 ± 4. 5 ） % ,P = O. 03 ] in MI ± MSC group than in MI ± PBS group. （ 2 ） Myofibroblasts congregating in the infarct region was significantly enhanced in MI ± MSC group compared with MI ± PBS group [ （ 196 _± 20 ） cells/ram2 vs. （ 89 _± 25 ） cells/mm2, t9 〈 0. 01 ], and part of implanted MSC expressed α-SMA＋ . （ 3 ） TGF-β1 expression and the phosphorylating of Smad2 in the infarct region were significantly upregulated in MI ± MSC group compared with MI ± PBS group （ all P 〈 0.05 ）. Conclusions MSC could improve myocardial function and promote myofihroblasts congregating in the infarct region via activating the TGF-β - Smad2 signaling pathway in this model.

关 键 词：心肌梗死 间质干细胞 心室重构 肌纤维母细胞 

分 类 号：R542.22[医药卫生—心血管疾病]