Characterization of long-term cultured c-kit+ cardiac stem cells derived from adult rat hearts.
Previous studies have revealed c-kit-positive (c-kit(+)) cardiac stem cells (CSCs) in the adult mammalian heart and these cells could be a suitable cell source for heart regeneration therapy. However, these cells have not been fully evaluated in terms of characterization and effect of long-term culture, which is necessary for their safe and optimal usage. Therefore, we isolated c-kit(+) CSCs from adult rat hearts to characterize these cells and investigate stability over long-term culture. We performed isolations of c-kit(+) CSCs 11 times and passaged them 40 times in a bulk culture system; we termed these cultures, bulk culture CSCs (CSC-BC). c-kit(+) CSCs expressed stemness genes and exhibited stem cell properties of single cell-derived clone formation, cardiosphere generation, and potential to differentiate into the three main cardiac lineages: cardiomyocyte, smooth muscle, and endothelial cells in vitro. Over long-term culture, some CSC-BC up-regulated GATA-4 expression, which resulted in enhanced cardiomyocyte differentiation, suggesting that the GATA-4 high c-kit(+) CSCs have potent cardiac regenerative potential. We also observed the spontaneous differentiation into cells other than cardiac lineages, such as adipocyte and skeletal myocyte. This effect of long-term culture on the c-kit(+) CSCs has not been previously reported. Interestingly, when c-kit(+) CSCs were co-cultured with adult rat cardiomyocytes, we found increased cardiomyocyte survival, and the growth factors, insulin-like growth factor 1 (IGF-1) and vascular endothelial growth factor (VEGF), appeared to be responsible factors. The present study suggests that c-kit(+) CSCs have great therapeutic potential yet should be further investigated and optimized as a cell source for regenerative therapies prior to transplantation.
Miyamoto
Shinka
S
Department of Cardiovascular Surgery, Heart Institute of Japan, Tokyo Women's Medical University, Tokyo, Japan.
Kawaguchi
Nanako
N
Ellison
Georgina M
GM
Matsuoka
Rumiko
R
Shin'oka
Toshiharu
T
Kurosawa
Hiromi
H
D017667:Adipocytes / Q000502:physiology; D053687:Adult Stem Cells / Q000166:cytology* / Q000378:metabolism / Q000502:physiology*; D000367:Age Factors; D000818:Animals; D018929:Cell Culture Techniques; D002454:Cell Differentiation; D049109:Cell Proliferation; D002469:Cell Separation; D002478:Cells, Cultured; D018485:Muscle Fibers, Skeletal / Q000502:physiology; D009206:Myocardium / Q000166:cytology* / Q000378:metabolism; D032383:Myocytes, Cardiac / Q000166:cytology / Q000502:physiology; D019009:Proto-Oncogene Proteins c-kit / Q000378:metabolism*; D051381:Rats; D011917:Rats, Inbred Lew; D055647:Rats, Transgenic; D017208:Rats, Wistar; D013997:Time Factors
D019009:Proto-Oncogene Proteins c-kit