Ergostane-Type Steroids from Korean Wild Mushroom Xerula furfuracea that Control Adipocyte and Osteoblast Differentiation

As part of our current projects to discover structurally and/or biologically novel compounds from Korean wild mushrooms, we isolated five ergostane-type steroids (1-5) from the fruiting bodies of Xerula furfuracea via repeated column chromatographic separations and HPLC purification. The chemical structures of the isolated steroids were shown to be (22E,24R)-24-methylcholesta-4,22-diene-3,6-dione (1), ergosta-7,22-diene-3β,5α,6β-triol (2), ergosta-7,22-diene-3β,5α,6β,9α-tetraol (3), (22E,24R)-5α,8α-epidioxyergosta-6,22-diene-3β-ol-3-O-β-D-glucopyranoside (4), and (22E,24R)-5α,8α-epidioxyergosta-6,9,22-triene-3β-ol-3-O-β-D-glucopyranoside (5) based on comparing the data regarding their spectroscopic and physical properties with those of previous studies. Notably, this is the first report of the presence of the identified steroids (1-5) in this mushroom. Compounds 1-5 were then tested to determine their effects on adipogenesis and osteogenesis in the mouse mesenchymal stem cell line C3H10T1/2. We found that compounds 4 and 5 suppressed the differentiation of stem cells into adipocytes. Notably, in addition to its suppressive effect on adipogenesis, compound 5 was also shown to promote the osteogenic differentiation of stem cells. These findings demonstrate that the bioactive compounds isolated might be effective for the treatment of menopause-associated syndromes, such as osteoporosis and obesity, as the isolated compounds were shown to suppress adipogenesis and/or promote osteogenesis of stem cells.

Keywords: Physalacriaceae; Xerula furfuracea; adipogenesis; ergostane-type steroids; osteogenesis.