Background Human umbilical cord blood contains an abundance of immature stem/progenitor cells, which may participate in the repair of hearts that have been damaged by myocardial infarction （MI）. This study aimed to ...Background Human umbilical cord blood contains an abundance of immature stem/progenitor cells, which may participate in the repair of hearts that have been damaged by myocardial infarction （MI）. This study aimed to evaluate the effects of human umbilical cord blood mononuclear cells （hUCBC） transplantation on cardiac function and left ventricular remodeling in rat model of MI. Methods Forty-five male Wistar rats were randomized into three groups： MI or control group （n=15）, MI plus cell transplantation （n=15）, and sham group （n=15）. Acute myocardial infarction （AMI） was established by ligating the left anterior descending artery, thereafter, hUCBC were implanted into the marginal area of infarcted myocardium. In MI/control group, DMEM was injected instead of hUCBC following the same protocol. Left ventricular function assessment was carded out by echocardiography and invasive hemodynamic measurements one month post MI. All rats were sacrificed for histological and immunochemical examinations.Results The transplanted hUCBC survived and engaged in the process of myocardial repair in the host heart. Echocardiography demonstrated that left ventricular function improved significantly in the rats that underwent cell transplantation. Hemodynamic studies found a significantly decreased left ventricular end-diastolic pressure （LVEDP） [（21.08±8.10） mmHg vs （30.82±9.59） mmHg, P〈0.05], increase in ＋dp/dtmax [（4.29± 1.27） mmHg/ms vs （3.24±0.75） mmHg/ms, P〈0.05）, and increase in -dp/dtmax [（3.71 ±0.79） mmHg/ms vs （3.00± 0.49） mmHg/ms, P〈0.05] among MI group with hUCBC transplantation when compared with MI/control group. Masson＇s trichrome staining revealed that the collagen density in the left ventricle was significantly lower in rats of transplantation group than that in the MI control groups [（6.33±2.69）% vs （11.10±3.75）%, P〈 0.01]. Based on immunostaining of α-actin, the numbers of microvessels were significantly （P〈0.01） increased at展开更多
Background Mesenchymal stem cells （MSCs） transplantation provides a new approach for myocardial repair. However, many important fundamental questions about MSCs transplantation remain unanswered. There is an urgent ...Background Mesenchymal stem cells （MSCs） transplantation provides a new approach for myocardial repair. However, many important fundamental questions about MSCs transplantation remain unanswered. There is an urgent need to identify MSCs from the beating heart and analyze the efficacy of this new approach. This study aimed to localize the magnetically labeled MSCs （MR-MSCs） and monitor the restorative effects of MR-MSCs with magnetic resonance （MR） imaging. Methods Acute myocardial infarction （AMI） was created in swine by a balloon occlusion of the left anterior descending coronary artery. Cells were delivered via intracoronary infusion after myocardial infarction. Infarct size change and cardiac function were assessed with 3.0T MR scanner. The results were then confirmed by histological and western blot analysis. All statistical procedures were performed with Systat （SPSS version 12.01）. Results A total of 26 swine were divided into four groups （sham-operated group, n=6; AMI group with PBS transplantation, n=6; labeled MSCs group, n=7; unlabeled MSCs group, n=7）. MSCs, MR-MSCs （10~cells） or PBS were delivered by intracoronary injection after MI and serial cardiac MR imaging studies were performed at 0, 4 and 8 weeks after transplantation. MR imaging demonstrated MI size decreased after MSCs transplantation in labeled and unlabeled groups, however, increases were seen in the AMI group at 8 weeks after MI. The left ventricular ejection fraction （LVEF） was slightly increased in the AMI group （（41.87~2.45）% vs （39.04~2.80）%, P 〉0.05）, but significantly improved in the MR-MSCs group （（56.85~1.29）% vs （40.67~2.00）%, P 〈0.05） and unlabeled group （（55.38~1.07）% vs （41.78~2.08）%, P 〈0.05） at 8 weeks after treatment. MR-MSCs were further confirmed by Prussian blue and immunofluorescent staining. Western blot analysis demonstrated that there was an increased expression of cardiomyocyte markers such as myosin heavy chain and troponin T in the MSCs trea展开更多
基金This study was supported by the Research Fund of the Department of Guangdong Science and Technology （No. 2003C30603） and Natural Science Foundation of Guangdong （No. 5001680）.
文摘Background Human umbilical cord blood contains an abundance of immature stem/progenitor cells, which may participate in the repair of hearts that have been damaged by myocardial infarction （MI）. This study aimed to evaluate the effects of human umbilical cord blood mononuclear cells （hUCBC） transplantation on cardiac function and left ventricular remodeling in rat model of MI. Methods Forty-five male Wistar rats were randomized into three groups： MI or control group （n=15）, MI plus cell transplantation （n=15）, and sham group （n=15）. Acute myocardial infarction （AMI） was established by ligating the left anterior descending artery, thereafter, hUCBC were implanted into the marginal area of infarcted myocardium. In MI/control group, DMEM was injected instead of hUCBC following the same protocol. Left ventricular function assessment was carded out by echocardiography and invasive hemodynamic measurements one month post MI. All rats were sacrificed for histological and immunochemical examinations.Results The transplanted hUCBC survived and engaged in the process of myocardial repair in the host heart. Echocardiography demonstrated that left ventricular function improved significantly in the rats that underwent cell transplantation. Hemodynamic studies found a significantly decreased left ventricular end-diastolic pressure （LVEDP） [（21.08±8.10） mmHg vs （30.82±9.59） mmHg, P〈0.05], increase in ＋dp/dtmax [（4.29± 1.27） mmHg/ms vs （3.24±0.75） mmHg/ms, P〈0.05）, and increase in -dp/dtmax [（3.71 ±0.79） mmHg/ms vs （3.00± 0.49） mmHg/ms, P〈0.05] among MI group with hUCBC transplantation when compared with MI/control group. Masson＇s trichrome staining revealed that the collagen density in the left ventricle was significantly lower in rats of transplantation group than that in the MI control groups [（6.33±2.69）% vs （11.10±3.75）%, P〈 0.01]. Based on immunostaining of α-actin, the numbers of microvessels were significantly （P〈0.01） increased at
基金Science Foundation of China （No. 30570743 and No. 30670853） and Pre-investigation Item of the Southeast University for Natural Science Foundation of China （No. XJ0590216）.
文摘Background Mesenchymal stem cells （MSCs） transplantation provides a new approach for myocardial repair. However, many important fundamental questions about MSCs transplantation remain unanswered. There is an urgent need to identify MSCs from the beating heart and analyze the efficacy of this new approach. This study aimed to localize the magnetically labeled MSCs （MR-MSCs） and monitor the restorative effects of MR-MSCs with magnetic resonance （MR） imaging. Methods Acute myocardial infarction （AMI） was created in swine by a balloon occlusion of the left anterior descending coronary artery. Cells were delivered via intracoronary infusion after myocardial infarction. Infarct size change and cardiac function were assessed with 3.0T MR scanner. The results were then confirmed by histological and western blot analysis. All statistical procedures were performed with Systat （SPSS version 12.01）. Results A total of 26 swine were divided into four groups （sham-operated group, n=6; AMI group with PBS transplantation, n=6; labeled MSCs group, n=7; unlabeled MSCs group, n=7）. MSCs, MR-MSCs （10~cells） or PBS were delivered by intracoronary injection after MI and serial cardiac MR imaging studies were performed at 0, 4 and 8 weeks after transplantation. MR imaging demonstrated MI size decreased after MSCs transplantation in labeled and unlabeled groups, however, increases were seen in the AMI group at 8 weeks after MI. The left ventricular ejection fraction （LVEF） was slightly increased in the AMI group （（41.87~2.45）% vs （39.04~2.80）%, P 〉0.05）, but significantly improved in the MR-MSCs group （（56.85~1.29）% vs （40.67~2.00）%, P 〈0.05） and unlabeled group （（55.38~1.07）% vs （41.78~2.08）%, P 〈0.05） at 8 weeks after treatment. MR-MSCs were further confirmed by Prussian blue and immunofluorescent staining. Western blot analysis demonstrated that there was an increased expression of cardiomyocyte markers such as myosin heavy chain and troponin T in the MSCs trea
