移植时机对骨髓间充质干细胞修复梗死心肌的影响

目的:观察心肌梗死后不同炎症微环境对骨髓间充质干细胞(MSCs)移植后在大鼠梗死心肌中的定位、存活及分化情况,探讨细胞治疗的最佳时间窗. 方法:建立大鼠左冠状动脉结扎的心肌梗死模型,心肌梗死后1 h及1,2,4,8 wk分别取心脏进行组织学观察;将经过4',6-二脒-2-苯基吲哚(4',6-diamidino-2-phenylindole, DAPI)标记的同种骨髓间充质干细胞在心肌梗死后1 h及1,2,4,8 wk移植到心肌梗死边缘区(每组n=10),对照组心肌梗死后1 h注射等量培养基(n=10). 心肌梗死后不同时间点采集心脏标本进行HE染色观察炎症反应的变化,细胞移植治疗各组在心肌梗死后8 wk测定心脏功能、心脏瘢痕面积以及免疫组化染色鉴定细胞分化情况. 结果:分离纯化的大鼠MSCs经流式细胞术鉴定为CD44 CD90 /CD34-CD45-CD31-,心肌梗死后1 wk梗死相关区的炎症反应较强,2 wk时减弱, 4～8 wk时瘢痕完全形成并出现左室重塑. 1 wk移植组未发现有移植细胞存活, 左室心功能及瘢痕面积百分比与对照组相似,1 h及2,4 wk细胞移植组心肌组织冰冻切片中可观察到大量标记细胞存在,并向周围迁移分布,免疫组化显示阳性标记细胞desmin, ctnI 阳性,左室血流动力学指标及瘢痕面积百分比与对照组比较均有改善(P<0.05), 2 wk的左室收缩末压力、左室最大上升速率及瘢痕面积百分比的改善优于1 h组和4 wk移植组(P<0.05). 结论:心肌梗死后炎症反应强烈, 不利于移植细胞的存活,而在炎症减弱的瘢痕修复早期尽早进行MSCs移植可能对于细胞的存活及心功能的恢复较为有利.     

Improvement of cardiac function after transplantation of autologous bone marrow mesenchymal stem cells in patients with acute myocardial infarction

Background The infarct size determines the long-term prognosis of patients with acute myocardial infarction (AMI). There is a growing interest in repairing scar area by transplanting bone marrow stem cells. However, effectiveness of intracoronary injection of bone marrow mesenchymal stem cells (BMSCs) in patients with AMI still remains unclear.Methods Sixty-nine patients with AMI after percutaneous coronary intervention (PCI) were randomly divided into intracoronary injection of BMSCs (n=34) and saline (control group, n=35) groups. Serial single positron emission computer tomography (SPECT), cardiac echo and cardiac electromechanical mapping were done at the designed time intervals until six months after transplantation of BMSCs or injection of saline. Results The proportion with functional defect decreased significantly in the BMSCs patients after three months ［(13±5)%］ compared with that pre-transplantation ［(32±11)%］ and the control group ［(28±10)%］ at three month follow-up (P&lt;0.05, respectively). Wall movement velocity over the infracted region increased significantly in the BMSCs group ［(4.2±2.5) cm/s vs (2.2±1.3) cm/s, P&lt;0.05］, but not in the control group ［(2.2±1.5) cm/s vs (2.7±1.7) cm/s, P&gt;0.05］. Left ventricular ejection fraction (LVEF) three months after transplantation in BMSCs group increased significantly compared with that pre-implantation and with that of the control group at three months post-injection ［(67±11)% vs (49±9)% and (53±8)%, P&lt;0.05 respectively］. SPECT scan results showed that perfusion defect was improved significantly in BMSCs group at three-month follow-up compared with that in the control group ［(134±66)cm2 vs (185±87)cm2, P&lt;0.01］. At the same time, left ventricular end-diastolic volume ［(136±31) ml vs (162±27) ml, P&lt;0.05］ and end-systolic volume ［(63±20) ml vs (88±19) ml, P&lt;0.05］ decreased synchronously. The ratio of end-systolic pressure to end-systolic volume ［Psyst/ESV, (2.84±1.30) mmHg/ml vs (1.72±1.23) mmHg/ml, P&lt;0.05］ increased significantly. Cardiac electromechnical mapping demonstrated significant improvement at three months after implantation of BMSCs compared with that pre-injection in both cardiac mechanical capability as left line local shorting ［LLS, (11.29±1.64)% vs (7.32±1.86)%, P&lt;0.05］ and electrical property as left ventricular endocardial unipolar voltage ［UV, (10.38±1.12) mV vs (7.61±1.09) mV, P&lt;0.01］; perfusion defect decreased from (36.2±6.2) % to (20.3±5.31)% (P&lt;0.01). Twenty-four-hour electrocardiographic monitoring demonstrated no arrhythmias occurred at three-months follow-up.Conclusions The transplantation of BMSCs might improve the cardiac function and it is safe and feasible with no deaths or malignant arrhythmias.     

药物干预骨髓间充质干细胞治疗急性心肌梗死的实验研究

目的 :观察炎症抑制因子IL -10干预后静脉移植骨髓间充质子细胞 (mesenchymalstemcells ,MSCs)与心外膜注射MSCs疗效的比较 ,探讨IL -10干预后静脉移植MSCs治疗心肌梗死的可行性。方法 :抽取大鼠股骨和胫骨骨髓 ,获得较纯MSCs ,溴氮胞苷 (BrdU)标记 ,配制成终浓度 3× 10 6/ml细胞悬液备用 ,制备IL -10溶液。结扎大鼠冠状动脉左前降支 ,建立急性心梗模型后随机分为 3组 ,对照组、IL- 10 +MSCs静脉移植组及MSCs心外膜注射组。 4周后处死大鼠 ,检测心肌内MSCs ,观察心脏结构和功能的改变。结果 :细胞移植 4周后可在心梗周边找到BrdU阳性标记的移植细胞。血流动力学和超声检查显示 ,与对照组相比 ,其它各组心脏结构和功能均明显改善 ,差异有统计学意义 (P <0 .0 5 ) ,而IL 10 +MSCs静脉移植组和MSCs心外膜注射组之间无明显差别 (P >0 .0 5 )。结论 :IL- 10 +MSCs静脉移植组和MSCs心外膜注射组均能明显改善心脏结构和功能且差异无统计学意义 ,故IL -10干预后静脉移植MSCs治疗心肌梗死可行。     

自体骨髓干细胞移植治疗心肌梗死的临床研究

目的研究自体骨髓干细胞经冠脉移植对心肌梗死患者心功能的影响及其安全性。方法6例冠心病伴心肌梗死患者,男5例、女1例,平均年龄62岁(51~75岁),体外分离培养自体骨髓干细胞2~3周,开通梗死相关“罪犯”血管,通过冠脉转运将骨髓干细胞植入患者的心肌梗死区,移植的骨髓间充质干细胞数为(0.9~3.2)×106个,骨髓单个核细胞数为(1.6~5.3)×106个。术前和术后6个月分别行99mTc-MIBI心肌灌注显像、二维超声心动图、心电图和动态心电图检查。结果6例患者二维超声心动图检查示左室射血分数(LVEF)较术前明显增加[(52.33±8.70)%vs(42.92±12.60)%,P<0.05],左室舒张期内径(LVDd)较术前明显减少[(54.33±4.84)vs(61.67±6.83),P<0.05];6例99mTc-MIBI检查显示梗死部位心肌灌注明显改善。术中及术后随访6~18个月无心律失常和其他合并症发生。结论进行自体骨髓干细胞经冠脉移植治疗冠心病、心肌梗死具有抑制左室重构、改善心脏功能的作用。     

Effects of heme oxygenase-1 gene modulated mesenchymal stem cells on vasculogenesis in ischemic swine hearts

Background  Mesenchymal stem cells (MSCs) transplantation may partially restore heart function in the treatment of acute myocardial infarction (AMI). The aim of this study was to explore the beneficial effects of MSCs modified with heme xygenase-1 (HO-1) on post-infarct swine hearts to determine whether the induction of therapeutic angiogenesis is modified by the angiogenic cytokines released from the implanted cells.

Methods  In vitro, MSCs were divided into four groups: (1) non-transfected MSCs (MSCs group), (2) MSCs transfected with the pcDNA3.1-Lacz plasmid (Lacz-MSCs group), (3) MSCs transfected with pcDNA3.1-hHO-1 (HO-1-MSCs group), and (4) MSCs transfected with pcDNA3.1-hHO-1 and pretreatment with an HO inhibitor, tin protoporphyrin (SnPP) (HO-1-MSCs+SnPP group). Cells were cultured in an airtight incubation bottle for 24 hours, in which the oxygen concentration was maintained at <1%, followed by 12 hours of reoxygenation. After hypoxia/reoxygen treatment, ELISA was used to measure transforming growth factor (TGF-β) and fibroblast growth factor (FGF-2) in the supernatant. In vivo, 28 Chinese mini-pigs were randomly allocated to the following treatment groups: (1) control group (saline), (2) Lacz-MSCs group, (3) HO-1-MSCs group, and (4) HO-1-MSCs + SnPP group. About 1×10⁷ of autologous stem cells or an identical volume of saline was injected intracoronary into porcine hearts 1 hour after MI. Magnetic resonance imaging (MRI) assay and postmortem analysis were assessed four weeks after stem cell transplantation.

Results  Post hypoxia/reoxygenation in vitro, TGF-β in the supernatant was significantly increased in the HO-1-MSCs ((874.88±68.23) pg/ml) compared with Lacz-MSCs ((687.81±57.64) pg/ml, P <0.001). FGF-2 was also significantly increased in the HO-1-MSCs ((1106.48±107.06) pg/ml) compared with the Lacz-MSCs ((853.85±74.44) pg/ml, P <0.001). In vivo, at four weeks after transplantation, HO-1 gene transfer increased the capillary density in the peri-infarct area compared with the Lacz-MSCs group (14.24±1.66/HPFs vs. 11.51±1.34/HPFs, P <0.001). Arteriolar density was also significantly higher in HO-1-MSCs group than in the Lacz-MSCs group (7.86±2.00/HPFs vs. 6.45±1.74/HPFs, P=0.001). At the same time, the cardiac function was significantly improved in the HO-1-MSCs group compared with the Lacz-MSCs group ((53.17±3.55)% vs. (48.82±2.98)%, P <0.05). However, all these effects were significantly abrogated by SnPP.

Conclusion  MSCs provided a beneficial effect on cardiac function after ischemia/reperfusion by the induction of therapeutic angiogenesis, and this effect was amplified by HO-1 overexpression.

     

骨髓间充质干细胞不同时期移植对心肌梗死大鼠心功能的影响

目的:探讨心肌梗死后骨髓间充质干细胞(MSCs)移植的最佳时间. 方法: 结扎大鼠左冠状动脉制备心肌梗死模型,将分离培养的大鼠MSCs经尾静脉分别移植到1 d, 1, 2, 4 wk移植组体内(各组n=10),对照组则注入等量培养液(n=10). 4 wk后测定左心功能指标和心肌缺血梗死面积. 结果: 心肌梗死后1 d移植组左心功能和心肌缺血梗死面积与对照组无明显差别(P＞0.05),而1, 2, 4 wk移植组与1 d移植组对比左心功能明显改善(P＜0.05),心肌缺血梗死面积显著减小(P＜0.05),其中2 wk移植组效果优于1 wk移植组和4 wk移植组(P＜0.05). 结论:心肌梗死后1～2 wk亚急性期进行细胞移植效果最好.     

曲美他嗪联合骨髓间质干细胞移植治疗急性心肌梗死的实验研究

目的探讨曲美他嗪(TMZ)能否改善骨髓间质干细胞(MSCs)在体外缺氧模型及急性心肌梗死(AMI)大鼠心脏的存活。方法加入或未加入TMZ的MSCs在无血清培养基培养并缺氧暴露12h,采用透射电子显微镜和流式细胞仪检查第3代MSCs的活力和凋亡。30只Wistar大鼠随机分为AMI对照组、MSCs组及(MSCs+TMZ)组,结扎左冠状动脉前降支制备AMI模型。将MSCs注入梗死心肌边缘[(MSCs组和(MSCs+TMZ)组)]。(MSCs+TMZ)组的大鼠在AMI前3d开始至AMI后28d加喂TMZ。移植28d后,超声心动图评估心脏结构和功能。免疫荧光染色检测移植细胞在体内的存活和分化。TUNEL法检测细胞凋亡。收集TMZ治疗开始前和AMI后24、48h的血液样本,测量C反应蛋白(CRP)与肿瘤坏死因子-α(TNF-α)的变化。结果缺氧培养下,TMZ处理过的MSCs细胞凋亡降低了一半。在体内与AMI对照组相比,MSCs组和(MSCs+TMZ)组的心肌梗死面积显著缩小,心功能明显改善。与单纯MSCs移植相比,TMZ与MSCs移植的组合治疗表现出了更低的干细胞凋亡、更高的干细胞存活、更小的心肌梗死面积和进一步改善的心功能。各组之间CRP、TNF-α的基线水平并无显著差异,然而24h时(MSCs+TMZ)组的所有参数均低于MSCs组。结论 MSCs移植添加TMZ治疗AMI增加MSCs存活和心脏功能的恢复上优于单纯MSCs移植,抑制炎症因子表达可能是其机制之一。     

自体脂肪干细胞治疗心肌梗死的实验研究

目的探讨自体脂肪干细胞治疗心肌梗死的作用机制。方法用9μmol/L的5-氮胞苷(5-aza)培养基诱导自体脂肪干细胞24h,2、3周后免疫细胞化学法染色鉴定心肌特异肌钙蛋白T(cTnT)和肌纤蛋白(desmin)的表达。冷冻法制作大鼠心肌梗死模型。1周后,经尾静脉移植自体脂肪干细胞。TTC染色测梗死体积,插管测左心室血流动力学变化。结果移植自体脂肪干细胞后,梗死体积减小(P<0.01),移植3w后,实验组左心室收缩压及左心室等容收缩期/舒张期内压最大上升或下降速率较对照组升高(P<0.05～0.01),左心室舒张末压较对照组减小(P<0.05)。结论经5-aza诱导的大鼠自体脂肪干细胞能减小心肌梗死体积及改善大鼠心肌梗死后的心脏功能。     

骨髓间质干细胞移植治疗急性心肌梗死的实验研究

目的通过两种不同移植途径研究骨髓间质干细胞治疗急性心肌梗死可行性及疗效对比。方法骨髓间质干细胞培养传至5代后,制备成浓度4×106/ml悬液备用。39只SD大鼠均结扎冠状动脉左前降支,制备成急性心肌梗死模型,随机分为3组每组各13只。Ⅰ为对照组:从尾静脉注射生理盐水。Ⅱ为直接经心外膜移植组:模型制备成功后1~3 h梗死周边区分六点注射骨髓间质干细胞,每点50μl。Ⅲ为通过静脉移植组:模型制备成功后24h,从尾静脉注射骨髓间质干细胞0.5 ml(含2×106个)连续7 d,Ⅰ和Ⅱ组注射等量生理盐水7 d作为对照。5周后,观察3组的大鼠死亡率以及心脏的结构和功能。结果Ⅰ组有3只大鼠死亡,其他组无死亡。与Ⅰ组相比,Ⅱ组和Ⅲ组的左心室结构与功能明显改善(P<0.05),Ⅱ组和Ⅲ组相比无明显差别(P>0.05)。结论骨髓间质干细胞移植治疗急性心肌梗死有效;静脉注射与直接经心外膜心肌注射两种途径无明显差别,静脉注射移植相对简单易行。     

经冠状动脉移植同种异体脐带间充质干细胞治疗猪心肌梗死的实验研究

目的：探讨经冠状动脉移植同种异体脐带间充质干细胞治疗急性心肌梗死（AMI）的可行性及疗效。方法采用经皮球囊封堵法制备 AMI 模型,AMI 后2周将 GFP 标记的脐带间充质干细胞经冠状动脉移植入小型猪心肌梗死区域（移植组）,对照组注射等量生理盐水。分别于干细胞移植前、移植后6周行心脏超声和核素门控心肌灌注显像检查,观察心肌灌注的改善及心功能的变化情况。取心肌梗死区组织作冰冻切片,vWF 免疫组织化学法染色观察梗死区毛细血管新生情况。结果（1）对照组：心肌梗死后8周和心肌梗死后2周比较,各项指标均无显著改善（P ＞0．05）。移植组：干细胞移植后6周左室射血分数、左室收缩期末内径、左室舒张末期内径、左室短轴缩短率及左室心肌梗死面积均较移植前有明显改善（P ＜0．05）。与对照组比较,移植组各项指标均明显改善（P ＜0．05）。（2）vWF 免疫组织化学法染色显示移植组新生毛细血管密度高于对照组。结论经冠状动脉移植的同种异体脐带间充质干细胞能够在梗死心肌内存活,增加梗死区血管新生,缩小梗死面积,改善心功能。     

Transplantation of autologous adipose-derived stem cells ameliorates cardiac function in rabbits with myocardial infarction

Background Adipose-derived stem cells （ADSCs） are capable of differentiating into cardiomyogenic and endothelial cells in vitro. We tested the hypothesis that transplantation of ADSCs into myocardial scar may regenerate infracted myocardium and restore cardiac function. Methods ADSCs were isolated from the fatty tissue of New Zealand white rabbits and cultured in Iscove＇s modified dulbecco＇s medium. Three weeks after ligation of left anterior descending coronary artery of rabbits, either a graft of untreated ADSCs （UASCs, n=14）, 5-azacytidine-pretreated ADSCs （AASCs, n=13）, or phosphate buffer saline （n=13） were injected into the infarct region. Transmural scar size, cardiac function, and immunohistochemistry were performed 5 weeks after cell transplantation. Results ADSCs in culture demonstrated a fibroblast-like appearance and expressed CD29, CD44 and CD105. Five weeks after cell transplantation, transmural scar size in AASC-implanted hearts was smaller than that of the other hearts. Many ADSCs were differentiated into cardiomyocytes. The AASCs in the prescar appeared more myotube-like. AASCs in the middle of the scar and UASCs, in contrast, were poorly differentiated. Some ADSCs were differentiated into endothelial cells and participate in vessel-like structures formation. All the ADSC-implanted hearts had a greater capillary density in the infarct region than did the control hearts. Statistical analyses revealed significant improvement in left ventricular ejection fraction, myocardial performance index, end-diastolic pressure, and peak ＋dP/dt, in two groups of ADSC-implanted hearts relative to the control hearts. AASC-implanted hearts had higher peak -dP/dt values than did control, higher ejection fraction and peak ＋dP/dt values than did UASC-implanted hearts. Conclusions ADSCs transplanted into the myocardial scar tissue formed cardiac islands and vessel-like structures, induced angiogenesis and improved cardiac function. 5-Azacytidine pretreatment before implantation is desirable for augmenting myogenesis. Transplantation of 5-azacytidine-treated ADSCs into the myocardial scar was more efficient than that of untreated ADSCs in preservation of cardiac function.     

Assessment of left ventricular segmental function after autologous bone marrow stem cells transplantation in patients with acute myocardial infarction by tissue tracking and strain imaging

Background Emerging evidence suggests that stem cells can be used to improve cardiac function in patients after acute myocardial infarction. In this randomized trial, we aimed to use Doppler tissue tracking and strain imaging to assess left ventricular segmental function after intracoronary transfer of autologous bone-marrow stem cells (BMCs) for 6 months’ follow up. Methods Twenty patients with acute myocardial infarction and anterior descending coronary artery occlusion proven by angiography were double-blindedly randomized into intracoronary injection of bone-marrow cell (treated, n=9) or diluted serum (control, n=11) groups. GE vivid 7 and Q-analyze software were used to perform echocardiogram in both groups 1 week, 3 months and 6 months after treatment. Three apical views of tissue Doppler imaging were acquired to measure peak systolic displacement (Ds) and peak systolic strain (εpeak) from 12 segments of LV walls. Left ventricular ejection fraction (LVEF), end-diastolic volume (EDV) and end-systolic volume (ESV) were obtained by Simposon’s biplane method. Results (1) 3 months later, Ds and εpeak over the infract-related region clearly increased in the BMCs group ［Ds: (4.49±2.71) mm vs (7.56±2.95) mm, P&lt;0.01; εpeak: (-13.40±6.00)% vs (-17.06±6.05)%, P&lt;0.01］, but not in the control group ［Ds: (4.74±2.67) mm vs (5.01±3.23) mm, P&gt;0.05; εpeak : (-13.84±6.05)% vs (-15.04±6.75)%, P&gt;0.05］. At the same time, Ds over the normal region also increased, but the Ds enhancement was markedly higher in the BMCs group than that in the control group ［(3.21±3.17) mm vs (0.76±1.94) mm, P&lt;0.01］. Parameters remained steady from the 3rd to 6th month in either group (P&gt;0.05). (2) LVEF in treated and control groups were almost the same at baseline (1st week after PCI) ［(53.37±8.92)% vs (53.51±5.84)%, P&gt;0.05］. But 6 months later, LVEF in the BMCs group were clearly higher than that in the control group ［(59.33±12.91)% vs (50.30±8.30)%, P&lt;0.05］. (3)There were no evident difference in EDV or ESV between two groups at baseline ［EDV:(113.74±23.24) ml vs (129.94±32.72) ml , P&gt;0.05; ESV: (57.12±18.66) ml vs (62.09±17.68) ml, P&gt;0.05］. Three months later, EDV and ESV in the control group were markedly greater than those in the BMCs group ［EDV: (154.89±46.34) ml vs (104.85±33.21) ml, P&lt;0.05; ESV :(82.91±35.79) ml vs (49.54±23.32) ml, P&lt;0.05］. But EDV and ESV did not change much from 3rd to 6th month in either group (P&gt;0.05). Conclusions Emergency transplantation of autologous BMCs in patients with acute myocardial infarction helps to improve global and regional contractility and attenuate post-infarction left ventricular remodeling. Tissue tracking and strain imaging provide quick, simple and noninvasive methods for quantifying left ventricular segmental function in humans.     

自体骨髓干细胞动员治疗心肌梗死

目的探讨基因重组人粒细胞集落刺激因子(rhGCSF)动员骨髓干细胞对急性心肌梗死动物模型的治疗作用。方法将60只SD大鼠随机分成对照组和治疗组,结扎冠状动脉左前降支建立大鼠心肌梗死实验模型。治疗组在复制大鼠心肌梗死模型3h后用经生理盐水稀释的rhGCSF(2mg·L-1)皮下注射10μg·kg-1·d-1,共5d;对照组复制大鼠心肌梗死模型3h后皮下注射等量生理盐水,共5d。在复制大鼠心肌梗死模型24、48h和2周后,两组分别先后各取10只大鼠行在体心功能(±dpdtmax)测定,测定完毕后各组随机选取6只大鼠处死行心脏梗死范围的测量,其余大鼠处死取出心脏行HE染色及CD34+免疫组织化学分析。结果结扎冠状动脉左前降支24、48h和2周后治疗组±dpdtmax均高于对照组(P<0.01);治疗组心脏梗死范围低于对照组(P<0.01)。病理检查显示对照组心肌梗死区周围有较多以中性粒细胞为主的炎症细胞浸润,而治疗组大鼠心肌坏死程度较对照组轻,浸润的细胞以CD34+的单个核细胞为主,并可见新生的心肌细胞生长。结论rhGCSF动员自体骨髓干细胞原位移植可修复梗死心肌、减少梗死范围、提高心功能,可用于急性心肌梗死的治疗。     

超声微泡辅助干细胞移植治疗急性心肌梗死的实验研究

目的:探讨超声微泡在自体骨髓间充质干细胞(BMMSCs)移植治疗猪急性心肌梗死(AMI)改善心功能中的作用。方法:选取14只3~4月龄小型家猪,抽取骨髓,分离、培养、标记BMMSCs,球囊封堵猪左冠状动脉前降支(LAD)建立AMI模型,分为实验组(超声微泡作用下移植干细胞,n=8)和对照组(无超声微泡作用,n=6),7 d后向LAD梗死处输注自体BMMSCs移植治疗。在移植前1 d和移植后6周分别行64层螺旋CT心脏扫描及组织病理学检查。结果:与对照组相比,实验组心功能改善更为明显,梗死区毛细血管数(16.37±3.20vs9.50±1.87,P<0.05)、普鲁士蓝染色阳性细胞数(71.63±14.09vs40.67±9.48,P<0.05)、结蛋白免疫组化染色阳性细胞数(31.88±4.16vs19.00±2.28,P<0.05)均明显增加。结论:超声微泡增效自体BMMSCs移植治疗AMI,能更有效地改善心肌梗死后的心功能,促进血管新生。     

间充质干细胞移植早期对心肌细胞凋亡及左心室功能的影响

目的 研究骨髓间充质干细胞(mesenchymal stem cells,MSC) 缺血心肌内移植早期对心肌细胞凋亡、血流动力学及左心室功能的影响.方法 采用密度梯度离心+ 贴壁培养方法分离培养Wistar 大鼠MSC,结扎左前降支建立急性心肌梗死(AMI)模型,结扎后30min 随机分为MSC 组( 于梗死边缘分4 点心肌内注射1×106 /0.1ml 的MSC,10 只),AMI 组( 同法心肌内注射PBS 0.1ml,10 只),假手术组(SHAM 组,5 只).监测细胞移植后72h 血流动力学、超声心动图及TUNEL 心肌细胞凋亡的变化.结果 与SHAM 组相比,AMI 大鼠血流动力学恶化,表现为平均动脉压、左心室收缩压明显下降,左心室舒张末压显著升高,左心室射血分数及缩短分数均显著降低,梗死及缺血区心肌细胞凋亡比例分别为41.6% 和18.9% ;MSC移植减少梗死及缺血区心肌细胞凋亡32% 和51%(P 均<0.01),但对大鼠的平均动脉压、左心室收缩压、左心室舒张末压及左心室功能无明显改善作用(P 均>0.05).结论 MSC 移植早期能减少心肌细胞凋亡但不改善急性心肌梗死后大鼠的心功能.     

老龄兔骨髓间充质干细胞移植治疗心肌梗死的最佳时间

目的:探讨老龄兔骨髓间充质干细胞(MSCs)移植治疗心肌梗死的最佳时间,为细胞移植治疗心肌细胞坏死性相关疾病提供前期的实验依据。方法：选择月龄大于或等于36个月的新西兰大耳白兔30只（36月　龄兔相当人60岁左右,为老龄兔）,建立心肌梗死模型,将造模成功兔随机分为6组（空白对照组、1 d组、1周组、2周组、3周组、4周组）,每组5只;取标记后的MSCs细胞（密度为2×10⁷•mL^-1）200 μL,分别多点注射于心肌梗死后1 d、1周、2周、3周、4周的心脏梗死区,空白对照组注射等量生理盐水。8周后进行心功能参数、心脏房室瓣血流率及血液动力学指标检测。结果：与对照组比较, 1 d移植组心功能参数、心脏房室瓣血流率及血液动力学指标高于对照组（P<0.05）;1周、2周及3周移植组心功能参数、心脏房室瓣血流率及血液动力学指标明显高于对照组（P<0.01）;4周移植组与对照组比较心功能虽有提高,但差异无显著性（P>0.05）;1周、2周及3周移植组心功能参数、心脏房室瓣血流率及血液动力学指标高于1 d移植组（P<0.05）;1周、2周、3周三组之间比较差异无显著性（P>0.05）。结论：心肌梗死后不同时间进行相同剂量细胞移植时,1 d~3周行MSCs细胞移植治疗均能改善心功能,以第1~3周移植效果最佳。     

经静脉骨髓基质干细胞移植治疗大鼠急性心肌梗死

目的:探讨急性心肌梗死(MI)早期经静脉途径移植骨髓基质干细胞(MSCs)对心肌梗死的影响。方法: 26只雄性SD大鼠随机分为Ⅰ组(MI+MSCs,n=10)、Ⅱ组(MI+PBS缓冲液,n=8)和Ⅲ组(假手术组,n=8),通过 结扎冠状动脉前降支制作心肌梗死模型。同种异体大鼠MSCs体外培养扩增,标记并通过尾静脉于MI后1d移植入 体内。分别进行心脏超声检查、血流动力学测定评价心功能,并行免疫组织化学分析。结果:MSCs移植3周后,Ⅰ组大 鼠心功能较Ⅱ组明显改善(P<0.05),其中Ⅰ组大鼠心功能较移植前也有明显改善(P<0.001),但Ⅱ组心功能则较移植 前进一步降低(P<0.001);免疫组化分析表明部分MSCs迁移至梗死心肌周围并存活下来,分化为心肌细胞。结论: 心肌梗死后1d,经静脉移植的MSCs可归巢至梗死心肌处,并分化为心肌细胞,从而改善损伤的心功能。