Bmi‐1 high‐expressing cells enrich cardiac stem/progenitor cells and respond to heart injury

• Published in: Journal of cellular and molecular medicine 2019-01, Vol.23 (1), p.104-111
• Main Authors: Song, Yuewang, Zhao, Mengmeng, Xie, Yuan, Zhu, Tingfang, Liang, Wenbin, Sun, Baiming, Liu, Weixin, Wu, Liqun, Lu, Guoping, Li, Tao‐Sheng, Yin, Tong, Xie, Yucai
• Format: Article
• Language: English
• Subjects: Animals; Bmi‐1; Cardiomyocytes; CD45 antigen; Cell Differentiation - genetics; Cell proliferation; Cell self-renewal; Cells, Cultured; Flow cytometry; Green Fluorescent Proteins - genetics; Green Fluorescent Proteins - metabolism; Heart; Heart Injuries - genetics; Heart Injuries - metabolism; Heart Injuries - physiopathology; infarction; Mice, Inbred C57BL; Mice, Transgenic; Microscopy, Confocal; Muscles; Myocardial infarction; Myocardial Infarction - genetics; Myocardial Infarction - metabolism; Myocardium - cytology; Myocardium - metabolism; Myocytes, Cardiac - metabolism; Original; Polycomb Repressive Complex 1 - genetics; Polycomb Repressive Complex 1 - metabolism; Progenitor cells; Proto-Oncogene Proteins - genetics; Proto-Oncogene Proteins - metabolism; RNA Interference; Side-Population Cells - metabolism; Smooth muscle; Stem cell transplantation; Stem cells; Stem Cells - metabolism; stem/progenitor cell
• ISSN: 1582-1838; 1582-4934
• DOI: 10.1111/jcmm.13889

Bmi‐1 gene is well recognized as an oncogene, but has been recently demonstrated to play a role in the self‐renewal of tissue‐specific stem cells. By using Bmi‐1GFP/+ mice, we investigated the role of Bmi‐1 in cardiac stem/progenitor cells and myocardial repair. RT‐PCR and flow cytometry analysis indicated that the expression of Bmi‐1 was significantly higher in cardiac side population than the main population from CD45−Ter119−CD31− heart cells. More Sca‐1+ cardiac stem/progenitor cells were found in Bmi‐1 GFPhi subpopulation, and these Bmi‐1 GFPhi heart cells showed the potential of differentiation into SMM+ smooth muscle‐like cells and TnT+ cardiomyocyte‐like cells in vitro. The silencing of Bmi‐1 significantly inhibited the proliferation and differentiation of heart cells. Otherwise, myocardial infarction induced a significantly increase (2.7‐folds) of Bmi‐1 GFPhi population, mainly within the infarction and border zones. These preliminary data suggest that Bmi‐1hi heart cells are enriched in cardiac stem/progenitor cells and may play a role in myocardial repair.