Abstract
Angiogenic factors such as bFGF have been incorporated in extracellular matrices to stimulate angiogenesis for tissue regeneration. However, the biological activity of protein-type growth factors did not last long because of their poor stability. Our previous studies have demonstrated that ginsenoside Rg1 (Rg1) and Re (Re) extracted from Panax ginseng are effective angiogenic factors. This study was designed to further investigate the stabilities of Rg1 and Re, using bFGF, a commonly used angiogenic factor, as a control. In the study, bFGF, Rg1, and Re were stored separately at different temperatures, pH values, and solvents for distinct durations. Subsequently, the remaining activity of each test agent on HUVEC proliferation, migration, and tube formation were studied in vitro. Additionally, angiogenesis in a Matrigel plug incorporated with bFGF, Rg1 or Re implanted subcutaneously in a C57/BL6 mouse model was investigated. The in vitro results showed that the activity of bFGF on proliferation, migration, and tube formation of HUVECs was significantly affected by its storage temperature, pH and solvent, while that of Rg1 or Re remained the same. Additionally, the in vivo results demonstrated that bFGF induced angiogenesis in a storage-condition-dependent manner, but neither Rg1 nor Re was significantly affected. The aforementioned results suggested that the stabilities of Rg1 and Re are significantly greater than that of bFGF.