RESUMO
Objective: To study the effects of Tongxinluo, a traditional Chinese medicine, on the proliferation of peripheral blood-derived endothelial progenitor cells (EPCs) in vitro. Methods: The Tongxinluo solution was prepared through ultrasonication according to the pervious literature. The mononuclear cells (MNCs) were isolated from the peripheral blood with Ficoll by density gradient centrifugation. MNCs were suspended in Medium 199 containing 20% fetal blood serum (FBS) and vascular endothelial growth factor (VEGF). After cultured for 7 d, the attached cells were characterized by Di-LDL uptaking and FITC-lectin binding by laser confocal microscope, and further identified through detection of CD34 and CD133 expression by flow cytometry. Then the cultured EPCs were incubated with Tongxinluo at a series of concentrations (0, 50, 100, 200, 500, 750, 1 000 μg/ml) for different durations (0, 6, 12, 24 and 36 h). The cell morphology was observed and cell proliferation was determined by MTT assay. Results: Incubation with different concentrations of Tongxinluo increased the proliferative ability of EPCs. Tongxinluo at 500 μg/ml had the most prominent effect on proliferation and the effect increased as time went by and reached peak at 36 h (growth rate 54.18%, P<0.01). Conclusion: Tongxinluo can greatly improve the proliferation of EPCs in vitro.