近日，Vanderbilt大学的研究者发现：位于冠状动脉的内皮细胞可以充当心脏干细胞功能，以产生新的心脏肌肉组织。
研究结论最近发表在Cell Reports杂志上，可帮助深入了解心脏如何保持本身，并可能便于寻找到心脏病发作后修复心脏新的策略。
心脏一直被认为是没有再生能力的器官，Antonis Hatzopoulos博士说：但是，最近的研究结果已经证明，其实低速率的新心脏肌肉细胞生成提示了心脏干细胞的存在。但这些细胞的来源是未知的。
Hatzopoulos和他的同事推测，位于血管的内皮细胞可能有产生新心脏细胞的潜力。他们知道，内皮细胞在发育过程能产生其他类型的细胞，包括血细胞。
现在，使用复杂的技术，追踪小鼠模型中细胞，他们已经证明在健康的心脏中，冠状动脉中的内皮细胞产生新的心肌细胞。他们发现冠状动脉中有两类心脏干细胞群，一类静息的心脏干细胞群，位于血管中膜层，一类增殖类型的心脏干细胞群位于血管外膜层。
我们的研究表明，冠状动脉疾病不仅可通过阻断血管造成心脏病发作，还能影响到心脏的维持和心脏细胞的再生方式来导致心脏衰竭。在先前的研究中，Hatzopoulos和同事证明心脏病发作后，内皮细胞转变成能产生瘢痕组织的成纤维细胞。看起来，一样内皮细胞系统在动态平衡过程中产生肌细胞，然后在心肌梗死中切换到生成疤痕组织。也即受伤后，再生变成纤维化。
doi:10.1016/j.celrep.2014.06.004
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PMID:
Endothelial Cells Contribute to Generation of Adult Ventricular Myocytes during Cardiac Homeostasis
Bryan A. Fioret, Jeremy D. Heimfeld, David T. Paik, Antonis K. Hatzopoulos
Cardiac tissue undergoes renewal with low rates. Although resident stem cell populations have been identified to support cardiomyocyte turnover, the source of the cardiac stem cells and their niche remain elusive. Using Cre/Lox-based cell lineage tracing strategies, we discovered that labeling of endothelial cells in the adult heart yields progeny that have cardiac stem cell characteristics and express Gata4 and Sca1. Endothelial-derived cardiac progenitor cells were localized in the arterial coronary walls with quiescent and proliferative cells in the media and adventitia layers, respectively. Within the myocardium, we identified labeled cardiomyocytes organized in clusters of single-cell origin. Pulse-chase experiments showed that generation of individual clusters was rapid but confined to specific regions of the heart, primarily in the right anterior and left posterior ventricular walls and the junctions between the two ventricles. Our data demonstrate that endothelial cells are an intrinsic component of the cardiac renewal process.
研究结论最近发表在Cell Reports杂志上，可帮助深入了解心脏如何保持本身，并可能便于寻找到心脏病发作后修复心脏新的策略。
心脏一直被认为是没有再生能力的器官，Antonis Hatzopoulos博士说：但是，最近的研究结果已经证明，其实低速率的新心脏肌肉细胞生成提示了心脏干细胞的存在。但这些细胞的来源是未知的。
Hatzopoulos和他的同事推测，位于血管的内皮细胞可能有产生新心脏细胞的潜力。他们知道，内皮细胞在发育过程能产生其他类型的细胞，包括血细胞。
现在，使用复杂的技术，追踪小鼠模型中细胞，他们已经证明在健康的心脏中，冠状动脉中的内皮细胞产生新的心肌细胞。他们发现冠状动脉中有两类心脏干细胞群，一类静息的心脏干细胞群，位于血管中膜层，一类增殖类型的心脏干细胞群位于血管外膜层。
我们的研究表明，冠状动脉疾病不仅可通过阻断血管造成心脏病发作，还能影响到心脏的维持和心脏细胞的再生方式来导致心脏衰竭。在先前的研究中，Hatzopoulos和同事证明心脏病发作后，内皮细胞转变成能产生瘢痕组织的成纤维细胞。看起来，一样内皮细胞系统在动态平衡过程中产生肌细胞，然后在心肌梗死中切换到生成疤痕组织。也即受伤后，再生变成纤维化。
doi:10.1016/j.celrep.2014.06.004
PMC:
PMID:
Endothelial Cells Contribute to Generation of Adult Ventricular Myocytes during Cardiac Homeostasis
Bryan A. Fioret, Jeremy D. Heimfeld, David T. Paik, Antonis K. Hatzopoulos
Cardiac tissue undergoes renewal with low rates. Although resident stem cell populations have been identified to support cardiomyocyte turnover, the source of the cardiac stem cells and their niche remain elusive. Using Cre/Lox-based cell lineage tracing strategies, we discovered that labeling of endothelial cells in the adult heart yields progeny that have cardiac stem cell characteristics and express Gata4 and Sca1. Endothelial-derived cardiac progenitor cells were localized in the arterial coronary walls with quiescent and proliferative cells in the media and adventitia layers, respectively. Within the myocardium, we identified labeled cardiomyocytes organized in clusters of single-cell origin. Pulse-chase experiments showed that generation of individual clusters was rapid but confined to specific regions of the heart, primarily in the right anterior and left posterior ventricular walls and the junctions between the two ventricles. Our data demonstrate that endothelial cells are an intrinsic component of the cardiac renewal process.
