P-49 茶樹茸(Agrocybe chaxingu)由来の破骨細胞形成阻害物質(ポスター発表の部) P-49 Osteoclast Forming Suppressive Compounds from the Mushroom Agrocybe chaxingu
Osteoporosis is caused by an imbalance between bone resorption and bone formation, which results in bone loss and fractures after mineral flux. Osteoclast-like multinucleated cells can be differentiated in vitro from co-cultures of mouse bone marrow cells and osteoblastic cells by treatment with osteotropic factors, 1α,25-dihydroxyvitamin D3 (1α,25(OH)_2D_3) and prostaglandin E2 (PGE2). During screening for osteoclast-formation suppressing effects of the extracts of various mushrooms by using the assay, we found very strong activity in the extract of the mushroom Agrocybe chaxingu. Therefore, an attempt was made to isolate the active principles from mushroom and to determine their structures. Powder of the dried fruiting bodies of Agrocybe chaxingu was extracted with CH_2Cl_2, EtOAc and then EtOH. The CH_2Cl_2-soluble fraction only showed the suppressing activity. After repeated chromatography of the fraction, compounds 1 and 2 were purified as the active principles. Osteoclast differentiation was estimated by TRAP-(+) multinucleated cell formation. The addition of compound 1and 2 (3.1μg/ml, 6.8mM) reduced the number of TRAP-(+) multinucleated cells to 66% and 0%, respectively.
天然有機化合物討論会講演要旨集 49(0), 383-388, 2007