Paeoniflorin Derivaties from Peony Roots Affecting Osteoblastic and Osteoclastic Differentiation

Osteoporosis is one of the most common bone diseases in the elderly. Osteoporosis related bone fracture could seriously lower the quality of the elderly’s life. Thus, in this study, natural products which can treat or prevent osteoporosis without severe side effects have been searched. The ethanol extract of Paeonia lactiflora Pall (Paeoniceae) significantly increased the differentiation of MC3T3-E1 preosteoblastic cells determined by alkaline phosphatase assay. The bioassay-guided isolation of ethyl acetate fraction allowed to isolated 6 paeoniflorin derivatives and 2 catechins such as 4-O-methyl-moudanpioside C (1), 4-O-methylbenzoyloxypaeoniflorin (2), oxypaeoniflorin (3), (+)-catechin (4), catechuic acid (5), paeoniflorin (6), benzoylpaeoniflorin (7), albiflorin (8). Among them, 4-O-methylmoudanpioside C (1), 4-O-methylbenzoyloxypaeoniflorin (2), oxypaeoniflorin (3), benzoylpaeoniflorin (7) and albiflorin (8) significantly increased the ALP activity. Particularly, 4-O-methylmoudanpioside C (1), 4-O-methylbenzoyloxypaeoniflorin (2) were the most active. Furthermore, 4-O-methylbenzoyloxypaeoniflorin (2) significantly inhibited the osteoclastic differentiation of Raw264.7 cells. Taken together, the extract of Paeonia lactiflora and its active constituents, particularly, 4-O-methylbenzoyloxypaeoniflorin (2) could have a benefical effect on bone formation and promote bone health.