Osteoporosis treatment always aimed at keeping the balance of bone formation and
bone resorption. Recently,
prenyl group in natural products has been proposed as an active group to enhance the osteogenesis process.
Osthole has both the
prenyl group and bone-protective activities, but the relationship is still unknown. In this study we found that
osthole exerted a potent ability to promote proliferation and osteogenic function of rat bone marrow stromal cells and osteoblasts, including improved cell viability,
alkaline phosphatase activity, enhanced secretion of
collagen-I, bone morphogenetic protein-2,
osteocalcin and
osteopontin, stimulated
mRNA expression of
insulin-like growth factor-1, runt-related transcription factor-2, osterix, OPG (
osteoprotegerin), RANKL (receptor activator for nuclear factor-κB
ligand), and the ratio of OPG/RANKL, as well as increasing the formation of mineralized nodules. However,
7-methoxycoumarin had no obvious effects.
Osthole also inhibited osteoclastic
bone resorption to a greater extent than
7-methoxycoumarin, as shown by a lower
tartrate-resistant acid phosphatase activity and lower number and smaller area of resorption pits. Our findings demonstrate that
osthole could be a potential agent to stimulate bone formation and inhibit
bone resorption, and the
prenyl group plays an important role in these bone-protective effects.