Abstract: Objective To investigate the effects of bone marrow mesenchymal stem cells (BMSC) transplantation on angiogenesis and proliferation-apoptosis in ischemic myocardium. Methods BMSC isolated from male mice were transfused into female mice with isoproterenol-induced myocardial ischaemia via tail vein. This study included three groups: BMSC, untreated, and control groups. Five weeks after treatment, expression levels of sex-determining region of Y-chromosome (SRY) and vascular endothelial growth factor (VEGF) in myocardium were detected by fluorescent qRT-PCR. Collagen distribution was observed using sirius red staining. The protein expression of VEGF, proliferating cell nuclear antigen(PCNA) and caspase-3 was detected by immunohistochemistry. Results BMSC group had significantly higher expression of SRY （11.22±0.90 vs 1.05±0.47, P<0.05）. Compared with the untreated group, BMSC group had decreased levels of collagen content(3.44±0.84 vs 8.44±1.09, P<0.05) and caspase-3（0.46±0.11 vs 3.12±0.28, P<0.05）, and increased level of VEGF(14.19±0.37 vs 11.88±0.28, P<0.05) and PCNA(4.08±0.18 vs 0.64±0.05, P<0.05). Conclusion BMSC can home to ischemic myocardium. BMSC transplantation improve microvascular angiogenesis and regulate the proliferation and apoptosis in ischemic myocardium.

Key words: Bone marrow mesenchymal stem cell, Myocardial ischaemia, microvascular angiogenesis, Proliferation, Apoptosis