Antiosteoporotic activity of the water extract of Dioscorea spongiosa.

After 60 MeOH and water extracts of natural crude drugs were screened for their ability to stimulate osteoblast proliferation, four MeOH extracts (Cynomorium songaricum, Drynaria fortunei, Lycium chinense, Rehmannia glutinosa) and seven water extracts (Cornus officinalis, Dendrobium nobile, Dioscorea spongiosa, Drynaria fortunei, Eucommia ulmoides, Lycium chinensis, Viscum coloratum) showed that potent activities were evaluated for inhibition of osteoclast formation. The results indicated that the water extract of D. spongiosa not only showed the strongest stimulation of osteoblast proliferation but also possessed potent inhibitory activity aganist osteoclast formation, whereas it showed lower cytotoxicity in osteoblast and bone marrow cells. A further in vivo experiment determined the antiosteoporotic activity of this extract, in which it inhibited the decrease in cancellous bone mineral content, cancellous bone mineral density, and cortical bone mineral content of the proximal tibia in ovariectomized rats.