Synergy effects of Asperosaponin VI and bioactive factor BMP-2 on osteogenesis and anti-osteoclastogenesis

Osteoporosis is a reduction in skeletal mass due to the decrease of osteogenic ability and the activation of the osteoclastic function. Inhibiting bone resorption and accelerating the new bone formation is a promising strategy to repair the bone defect of osteoporosis. In this study, we first systematically investigated the roles of Chinese medicine Asperosaponin VI (ASP VI) on osteogenic mineralization of BMSCs and osteoclastogenesis of BMMs, and then explored the synergistic effect of ASP VI and BS (BMP-2 immobilized in 2-N, 6-O-sulfated chitosan) on bone formation. The result showed that ASP VI with the concentration lower than 10(-4) M contributed to the expression of osteogenic gene and inhibited osteoclastic genes RANKL of BMSCs. Simultaneously, ASP VI significantly reduced the differentiation of mononuclear osteoclasts in the process of osteoclast formation induced by M-CSF and RANKL. Furthermore, by stimulating the SMADs, TGF-beta 1, VEGFA, and OPG/RANKL signaling pathways, ASBS (ASP VI and BS) substantially enhanced osteogenesis, greatly promoted angiogenesis, and suppressed osteoclastogenesis. The findings provide a new perspective on osteoporosis care and prevention.