Regulation of c-kit+ progenitor cells by stromal cell derived factor-1α in adult murine heart

摘要

Background: c-kit-positive cardiac progenitor cells (CPCs) have been proven suitable for stem cell therapy. CPCs marker c-kit and its ligand, the stem cell factor (SCF), are associated with the functions of proliferation and differentiation. In our previous study, we found that stromal cell-derived factor-1α (SDF-1α) could enhance the expression of c-kit. However, the mechanism is unknown. Methods and results: CPCs were isolated from adult mouse hearts, and c-kit-positive CPCs were purified by magnetic-activated c-kit cell sorting magnetic beads. The cells were cultured with SDF-1α, c-kit expression was measured by western blotting and qPCR, the proliferation and migration of cells were measured by CCK-8 and transwell assay, DNA methyltransferase (DNMT) mRNA were measured by qPCR, global DNMT activity was measured by DNMT activity assay kit, and DNA methylation was analysed using Sequenom's MassARRAY platform. Results showed that SDF-1α could enhance the expression of c-kit, which results in the promoting of c-kit-positive CPCs proliferation and migration. SDF-1α stimulation inhibited the expression of DNMT1, DNMT3β, and global DNMT activity, which led to significant demethylation in c-kit-positive CPCs. Conclusions: SDF-1α signalling, via CXCR4 activation, up-regulated c-kit expression by inhibiting DNMT1 and DNMT3β expression and global DNMT activity, and by subsequent demethylation of the c-kit gene.