摘要
It has been a decade since the monumental discovery of resident stem cells in the mammalian heart, and the following studies witnessed the continuous turnover of cardiomyocytes and vascular cells, maintaining the homeostasis of the organ. Recently, the autologous administration of c-kit-positive cardiac stem cells in patients with ischemic heart failure has led to an incredible outcome; the left ventricular ejection fraction of the celltreated group improved from 30% at the baseline to 38% after one year and to 42% after two years of cell injection. The potential underlying mechanisms, before and after cell infusion, are explored and discussed in this article. Some of them are related to the intrinsic property of the resident stem cells, such as direct differentiation, paracrine action, and immunomodulatory function, whereas others involve environmental factors, leading to cellular reverse remodeling and to the natural selection of "juvenile" cells. It has now been demonstrated that cardiac stem cells for therapeutic purposes can be prepared from tiny biopsied specimens of the failing heart as well as from frozen tissues, which may remarkably expand the repertoire of the strategy against various cardiovascular disorders, including non-ischemic cardiomyopathy and congenital heart diseases. Further translational investigations are needed to explore these possibilities.
It has been a decade since the monumental discoveryof resident stem cells in the mammalian heart, and thefollowing studies witnessed the continuous turnoverof cardiomyocytes and vascular cells, maintaining thehomeostasis of the organ. Recently, the autologousadministration of c-kit-positive cardiac stem cells inpatients with ischemic heart failure has led to an incredibleoutcome; the left ventricular ejection fraction of the celltreatedgroup improved from 30% at the baseline to 38%after one year and to 42% after two years of cell injection.The potential underlying mechanisms, before and aftercell infusion, are explored and discussed in this article.Some of them are related to the intrinsic property of theresident stem cells, such as direct differentiation, paracrineaction, and immunomodulatory function, whereas othersinvolve environmental factors, leading to cellular reverseremodeling and to the natural selection of ＂juvenile＂ cells.It has now been demonstrated that cardiac stem cells fortherapeutic purposes can be prepared from tiny biopsiedspecimens of the failing heart as well as from frozentissues, which may remarkably expand the repertoireof the strategy against various cardiovascular disorders,including non-ischemic cardiomyopathy and congenitalheart diseases. Further translational investigations areneeded to explore these possibilities.
基金
The Japan Society for the Promotion of Science Grant-in-Aid for Scientific Research(C),No.25461118
