Study on alantolactoneinduced differentiation of mesenchymal stem cells into vascular cells

To promote efficient screening of active angiogenic drugs from traditional medicines, we constructed a human embryonic kidney293 cell model using vascular endothelial growth factor (VEGF) gene promoter as the drug target. In this model, VEGF gene promoter may regulate the expression of the luciferase reporter gene by responding to the stimulation of drug molecules. This cell model allows rapid and efficient screening of vascularinducing active components from several drug monomer molecules. Furthermore, we used rat bone marrow mesenchymal stem cells (rMSCs) to conduct a preliminary study on the activity of alantolactone. Using simvastatin as a positive control, we investigated the effects of alantolactone on the expression of vascularrelated cell marker molecules such as VEGF and αsmooth muscle actin (αSMA) in rMSCs. According to our results, 0.1, 1, 3 and 5 μM of alantolactone upregulated the transcriptional luciferase gene activity of VEGF promoter, and a significant difference from that in the control group was observed. Among them, 3μM of alantolactone showed the better effect than that of 3 μM of simvastatin (P=0.036) and other concentrations of alantolactone and simvastatin showed similar effects. Compared with that in the control group, rMSCs induced with 1μM alantolactone for 3 days showed a significant increase in the relative mRNA expressions of VEGF and αSMA genes. However, these effect of 5 μM alantolactone were weaker than those of 5 μM simvastatin (P lt;0.05); rMSCs treated with 1 μM alantolactone for 3 days showed brighter green fluorescence (FITC marker) of αSMA and VEGF in situ expression than that observed in the control group and similar fluorescence intensity than that of simvastatin group in an immunoradiometric assay. The above results demonstrate the reliability of the highly efficient system for screening of active drug molecules and confirmed the vascular induction function of alantolactone at the gene and protein levels.