Vegf Effects On Dental Pulp Stem Cells Proliferation And Differentiation

Objectives: The aim of this work was to investigate the effects of the peptide VEGF-A165 on the proliferation and osteogenic differentiation of human Dental Pulp Stem Cells (hDPSCs). Methods: Mesenchymal stem cells were obtained from dental pulp of enclosed thirds molars of young healthy patients. Mesenchymal markers expression was investigated by FACS analysis. Cell differentiation towards osteogenic or adipogenic lineages was evaluated by means of Alizarin Red S or Red Oil O staining, respectively. The expression of receptors (VEGF-1 and -2) and co-receptors (neuropilin-1 and -2) was estimated by RT-PCR. The effects of VEGF-A165 on cell proliferation was evaluated by MTT assay whereas Western Blot analysis was used to measure VEGF-induced changes in ALP and PECAM-1 protein content. Results: Cells, isolated from dental pulp, originated a homogenous population expressing typical mesenchymal markers (CD29, CD90, CD146, CD166 and STRO-1), able to differentiate into osteoblasts and adypocytes. RT-PCR analysis in undifferentiated or differentiating hDPSCs showed an equivalent expression of known VEGF receptors (VEGFR-1, VEGFR-2) and co-receptors (neuropilin-1 and -2), able to bind VEGF-A165. The VEGF-A165 (10-40 ng/ml) stimulation of undifferentiated hDPSCs for different periods (1-8 days) caused a dose- and time-dependent increase of cell proliferation rate. Moreover, the exposure of differentiating hDPSCs to 40 ng/VEGF-A165 increased ALP protein content without inducing the endothelial marker PECAM-1 expression. Additionally, VEGF-A165 stimulation induced CD90 decrease, not associated with variations of other investigated mesenchimal markers. Conclusions: The exposure of hDPSCs to the peptide VEGF-A165 stimulates their proliferation. The increase of ALP cell content coupled to the CD90 decrement suggests that VEGF activity on cell division does not reduce their osteogenic differentiation potential, thus confirming a property previously shown in cells deriving from bone marrow. Moreover, VEGF does not favor cell differentiation into a endothelial phenotype, likely due to a lack of an artificial in vitro support.