Guo J.,Cardiovascular Institute of Affiliated Hospital |
Jie W.,Guangdong Medical College |
Shen Z.,Guangdong Medical College |
Li M.,Hainan Medical College |
And 5 more authors.
International Journal of Molecular Medicine | Year: 2014
The transplantation of cardiac stem cells (CSCs) is thought to be responsible for improving the performance of injured heart induced by myocardial infarction (MI). However, the mechanisms involved in the migration of activated CSCs post-MI remain to be clarified. In this study, CSCs were isolated from rat hearts and a cellular migration assay was performed using a 24-well Transwell system. Stem cell factor (SCF) induced CSC migration in a concentration- dependent manner, which could be blocked with an SCF antibody as well as a PI3K/AKT inhibitor, LY294002. Moreover, SCF induced the expression and activity of matrix metalloproteinase (MMP)-2 and MMP-9 in a concentration and time-dependent manner, as measured by quantitative RT-PCR, western blot analysis and gelatin zymography. Results of western blot analysis revealed phosphorylated AKT was markedly increased in SCF-treated CSCs and that inhibition of SCF/c-Kit signaling or phospho-AKT activity significantly attenuated the SCF-induced expression of MMP-2 and MMP-9. Thus, our results showed that SCF partially mediated CSC migration via the activation of PI3K/AKT/MMP-2/-9 signaling.
Ding R.,Guangdong Medical University |
Jiang X.,Guangdong Medical University |
Ha Y.,Guangdong Medical University |
Wang Z.,Guangdong Medical University |
And 5 more authors.
Stem Cell Research and Therapy | Year: 2015
Introduction: Transplantation of bone marrow mesenchymal stem cells (BMSCs) can repair injured hearts. However, whether BMSC populations contain cells with cardiac stem cell characteristics is ill-defined. We report here that Notch signalling can promote differentiation of c-KitPOS/NKX2.5POS BMSCs into cardiomyocyte-like cells. Methods: Total BMSCs were isolated from Sprague-Dawley rat femurs and c-KitPOS cells were purified. c-KitPOS/NKX2.5POS cells were isolated by single-cell cloning, and the presence of cardiomyocyte, smooth muscle cell (SMC), and endothelial cell differentiation markers assessed by immunofluorescence staining and semi-quantitative reverse-transcription polymerase chain reaction (RT-PCR) analysis. Levels of c-Kit and Notch1-4 in total BMSCs and c-KitPOS/NKX2.5POS BMSCs were quantitated by flow cytometry. Following infection with an adenovirus over-expressing Notch1 intracellular domain (NICD), total BMSCs and c-KitPOS/NKX2.5POS cells were assessed for differentiation to cardiomyocyte, SMC, and endothelial cell lineages by immunofluorescence staining and real-time quantitative RT-PCR. Total BMSCs and c-KitPOS/NKX2.5POS cells were treated with the Notch1 ligand Jagged1 and markers of cardiomyocyte, SMC, and endothelial cell differentiation were examined by immunofluorescence staining and real-time quantitative RT-PCR analysis. Results: c-KitPOS/NKX2.5POS cells were present among total BMSC populations, and these cells did not express markers of adult cardiomyocyte, SMC, or endothelial cell lineages. c-KitPOS/NKX2.5POS BMSCs exhibited a multi-lineage differentiation potential similar to total BMSCs. Following sorting, the c-Kit level in c-KitPOS/NKX2.5POS BMSCs was 84.4%. Flow cytometry revealed that Notch1 was the predominant Notch receptor present in total BMSCs and c-KitPOS/NKX2.5POS BMSCs. Total BMSCs and c-KitPOS/NKX2.5POS BMSCs overexpressing NICD had active Notch1 signalling accompanied by differentiation into cardiomyocyte, SMC, and endothelial cell lineages. Treatment of total BMSCs and c-KitPOS/NKX2.5POS BMSCs with exogenous Jagged1 activated Notch1 signalling and drove multi-lineage differentiation, with a tendency towards cardiac lineage differentiation in c-KitPOS/NKX2.5POS BMSCs. Conclusions: c-KitPOS/NKX2.5POS cells exist in total BMSC pools. Activation of Notch1 signalling contributed to multi-lineage differentiation of c-KitPOS/NKX2.5POS BMSCs, favouring differentiation into cardiomyocytes. These findings suggest that modulation of Notch1 signalling may have potential utility in stem cell translational medicine. © 2015 Ding et al.; licensee BioMed Central.