Stimulation of Osteogenic Activity in Human Osteoblast Cells by Edible Uraria crinita

Uraria crinita is an edible herb used as a natural food for childhood skeletal dysplasia. Ethyl acetate, n-butanol, and aqueous fractions of a 95% ethanol crude extract of U. crinita were obtained and the active ingredients isolated and purified using a bioguided method. In this manner, we isolated and identified a new active flavone glycoside, apigenin 6-C-beta-D-apiofuranosyl(1 -> 2)-alpha-D-xylopyranoside (3) and 10 known components with stimulatory activity on human osteoblast cells. The new compound 3 at 100 mu M significantly increased alkaline phosphatase activity (114.10 +/- 4.41%), mineralization (150.10 +/- 0.80%), as well as osteopontin (1.39 +/- 0.01-fold), bone morphogenetic protein-2 (BMP-2, 1.30 +/- 0.04-fold), and runt-related transcription factor 2 (Runx2, 1.43 +/- 0.10-fold) mRNA expression through the activation of the BMP-2/Runx2 pathway. Two other components, dalbergioidin (1) and byzantionoside B (9), displayed similar effects. These results show that U. crinita and its active compounds may have the potential to stimulate bone formation and regeneration.