Cardiac myocytes are recruited by bone marrow-derived cells in intact murine heart.
It is generally believed that the cardiac myocytes withdraw from the cell cycle shortly after birth and thereafter any loss of myocardial tissue cannot be repaired. However, recent reports indicate that cardiac myocytes can be regenerated by stem cells derived from bone marrow in the damaged hearts. In this study, we investigated whether bone marrow-derived cells can differentiate into cardiac myocytes in the intact hearts. We performed bone marrow transplantation from syngenic male mice to female c57/B6 mice. In female mice's hearts, the presence of cells from male mice was examined by FISH method that detects Y chromosome. Using the same samples, we also performed immunohistochemical staining with muscle specific antibodies. In the heart sections of female mice, there were some cells that were considered as differentiated myocytes derived from male bone marrow (0.01~0.09% of total myocytes) and the proportion of the cells increased as the period after bone marrow transplantation became longer (3 months after vs. 8 months after). These results suggest that, not only in the damaged heart but also in the intact heart, a portion of cardiac myocytes is recruited by bone marrow-derived cells.
Satomi-Kobayashi
Seimi
S
Division of Cardiovascular and Respiratory Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan.
Kawashima
Seinosuke
S
Sakoda
Tsuyoshi
T
Ueyama
Tomomi
T
Kawai
Miki
M
Toh
Ryuji
R
Azumi
Hiroshi
H
Mizutani
Kazuo
K
Hattori
Kunihiro
K
Yokoyama
Mitsuhiro
M
D000818:Animals; D016026:Bone Marrow Transplantation; D019070:Cell Lineage; D005260:Female; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D023421:Models, Animal; D009206:Myocardium / Q000648:ultrastructure*; D032383:Myocytes, Cardiac / Q000502:physiology* / Q000648:ultrastructure*; D012016:Reference Values; D012038:Regeneration / Q000502:physiology; D012680:Sensitivity and Specificity; D033581:Stem Cell Transplantation; D014998:Y Chromosome