Maohuoside A acts in a BMP-dependent manner during osteogenesis

There has been a strong interest in searching for natural therapies for osteoporosis. Epimedium koreanum Nakai is an herb that is commonly used in East Asia to treat osteoporosis, and most studies of its activity have focused on its major ingredient, icariin. In this study, maohuoside A (MHA), a single compound isolated from the E. koreanum, was found to promote osteogenesis in mouse bone marrow-derived mesenchymal stem cells. We hypothesise that, if MHA potently induces osteogenic differentiation in a bone morphogenetic protein-dependent manner, it may be used to broaden the sources for cell transplantation and thereby establish more efficient bone regeneration systems. Real-time polymerase chain reaction and western blot were used to detect the expression of SMAD4, a marker of bone formation. Microcomputed tomography and histomorphometric techniques showed that oral treatment with MHA was followed by an increase in the bone mineral density of the lumbar vertebrae in mice. This result also indicates that MHA may directly activate osteopontin gene transcription. In conclusion, MHA seems to enhance the osteogenesis of bone marrow-derived mesenchymal stem cells at least partly via bone morphogenetic protein signalling.