Abstract:

Objective    To investigate the effects of the platelet-derived growth factor(PDGF) on the proliferation, extracellular matrix  synthesis and its probable mechanism in human umbilical cord mesenchymal stem cells(UCMSCs). Methods    Cultured UCMSCs were divided into 6 groups: the control group, and the PDGF-treated groups(2, 5, 10, 20 and 50μg/L).  Morphological changes of the cells were observed under an inverted microscope.  MTT assay was used to detect the PDGF effects on cell proliferation.  Expressions of ECM mRNA and apoptosis-related genes(Bcl-2, Bax)were detected by qRT-PCR. Results    With an increased concentration of PDGF, UCMSCs proliferation was gradually promoted compared with the control group. 20μg/L PDGF greatly promoted UCMSCs proliferation, however, 50μg/L showed  inhibitive effects. Expressions of ECM mRNA and apoptosis-related factor (Bcl-2/Bax) were down-regulated in the 2μg/L PDGF group but up-regulated when PDGF≥5μg/L. 10μg/L PDGF greatly upregulated ECM mRNA expression and apoptosis-related factor (Bcl2/Bax). Conclusion    PDGF can promote the proliferation of UCMSCs, stimulate ECM synthesis and improve the ability to withstand apoptosis of UCMSCs in vitro. 10μg/L PDGF was the most effective concentration.

Key words: Cord; Mesenchymal stem cells; Plateletderived growth factor; Extracellular matrix