Background: Evaluation of angiogenesis-inducing compounds is essential in tissue engineering to develop biological substitutes for the repair or regeneration of tissue function. In this report, we evaluated the angiogenic ability of ginsenoside Rg(1) from Panax ginseng, in Matrigel implanted on fluorescent transgenic mice. Methods: The in vitro proliferation ability of each test agent was estimated by MTS assay. The Matrigel loaded with basic fibroblast growth factor (bFGF) or Rg(1) and Matrigel alone were implanted on fluorescent transgenic mice and were retrieved at 1, 4, 6 and 8 weeks after implantation to measure various conventional markers for angiogenesis including neo-vascular density and hemoglobin content. Additionally, the functional neo-vasculature in the implanted Matrigel was visualized using confocal laser scanning microscopy (CLSM). Results: The in vitro results indicated that the stimulating effect of Rg(1) on HUVECs proliferation remained unchanged after dissolved for 30 days in culture medium at 37 degrees C when compared with the effect of bFGF. One week after implantation in transgenic mice, bFGF or Rg(1) mixed in Matrigel plug significantly enhanced angiogenesis; however, at 6 weeks a significant decrease in angiogenic effect was observed in Matrigel with bFGF, but not in Matrigel with Rg(1). The neo-vessels structure was visualized in three dimensions (3D) by CLSM and the results were in agreement with other conventional measurements for angiogenesis. Conclusion: These findings confirm that Rg(1) could be used in tissue tissue-engineering applications and that the fluorescent transgenic mice can be a useful experimental model for studying angiogenesis.
