骨髓间充质干细胞移植与肝细胞生长因子转导对猪心肌梗死后心力衰竭治疗作用的比较

Comparative study between bone marrow cell transplantation and Ad_5-HGF transfer via noninfarct-relative artery on neovascularization and heart function after myocardial infarction in swine

目的研究经猪非梗死相关动脉分别移植骨髓间充质干细胞(bone marrow-derivedmes-enchymal stem cells,BM-MSCs)或腺病毒介导肝细胞生长因子(adenovirus5-hepatocyte growth factor,Ad5-HGF)对心肌梗死的治疗作用。方法苏中幼猪18只,分为3组:BM-MSCs组、Ad5-HGF组与对照组。3组均经开胸结扎冠状动脉前降支制作心肌梗死模型。BM-MSCs组结扎后2周抽取骨髓分离培养BM-MSCs,并在结扎后4周经非梗死相关动脉注入梗死心脏(剂量5×106/mL)。Ad5-HGF组于结扎后4周经非梗死相关动脉注入Ad5-HGF4×109pfu。对照组则注入同样量的细胞培养液(IMDM)。三组均在结扎后4周和7周行门控心肌显像评价心肌灌注及心功能,并在7周处死动物,取心脏标本,行免疫组化检查。结果(1)免疫组化结果:在两治疗组与对照组梗死周边区均可见新生血管,BM-MSCs组和Ad5-HGF组的新生血管密度(毛细血管密度分别为102·4±8·6/mm2和105·3±7·7/mm2,功能血管密度分别为52·1±4·1/mm2和66·0±3·3/mm2)均高于对照组(毛细血管密度55·5±4·7/mm2,功能血管密度16·4±3·5/mm2),P均<0·01。(2)门控心肌显像:治疗后4周两治疗组及对照组间左室射血分数(LVEF)值差异均无统计学意义;治疗后7周BM-MSCs组和Ad5-HGF组LVEF值(45·0±2·7和43·9±4·3)明显优于对照组(30·4±2·8),差异均有统计学意义(P均<0·01);治疗组治疗后7周较4周时LVEF值明显好转(BM-MSCs组45·0±2·7比33·6±2·1,Ad5-HGF组43·9±4·3比32·2±1·8,P均<0·01),对照组前后LVEF值无明显变化;两治疗组LVEF值改善幅度相比,差异无统计学意义。结论经非梗死相关动脉移植BM-MSCs或Ad5-HGF均能促进梗死心脏心功能改善和促进血管再生,但未显示出二者之间何者更具优势。

Objective To evaluate the impact of transplanting bone marrow-derived mesenchymal stem cells （BM-MSCs） or adenoviruss-hepatocyte growth factor （Ad5-HGF） via noninfarction-related artery in swine myocardial infarction models. Methods BM-MSCs were obtained from swine bone marrow, expanded in vitro to a purity of 〉 50%. Myocardial infarction （ MI ） models were created by ligating the distal left anterior descending artery in swines （n = 18 ）. Either BM-MSCs cells （5 × 10^6/mL） （n = 6 ） or Ad5-HGF （4 × 10^9 pfu） （n =6） were transfused into infracted area via noninfarction-related artery at four weeks after MI. IMDM fluid was injected into the noninfarction-related artery in the control （ n = 6）. Gate cardiac perfusion imaging was performed at four and seven weeks after LAD ligation respectively to evaluate the heart function and cardiac perfusion. Morphologic and histologic characteristics of the hearts were also studied. Results （ 1 ） New vessels firnation was found around the infarction area in all the three groups. By means of immno-histological staining, the density of capillaries and vessels with function in the BM-MSCs group and the Ad5-HGF group were 102. 4±8.6/mm^2 and 105.3 ±7.7/mm^2, as well as 52. 1 ±4. 1/mm^2 and 66.0 ± 3.3/mm^2 respectively. Both vessel density were higher than those of the control （ 55.5± 4. 7/ mm^2 and 16.4 ± 3.5/mm^2, P 〈 0. 01 ）. （ 2 ） Left ventricular eiection fraction （LVEF） was similar among the 3 groups at 4 weeks. Improvement in LVEF was observed in the BM-MSCs group （45.0 ± 2. 7） and the Ad5 -HGF （43.9 ± 4. 3 ） group compared with the control （ 30. 4 ±2. 8, P 〈 0. 01 ） at 7 weeks. Improvement in LVEF was also observed within each treatment group by comparing the LVEF at 4 weeks with that at 7 weeks （ in BM-MSCs group ： 45.0 ± 2.7 vs 33.6± 2. 1, in Ads -HGF group ： 43.9± 4. 3 vs 32.2± 1.8, all P 〈 0. 01 ）. No statistical difference was found between the BM-MSCs group and the Ad5-HGF group in LVEF. Conclusion BM-MSCs or Ad5-HGF transplantation via noninfarction-related artery can stimulate angiogenesis and improve heart function, but neither BM-MSCs nor Ad5-HGF showed superiority in therapeutic results over each other.