Chemical Constituents from the Leaves of Manglietia phuthoensis and Their Effects on Osteoblastic MC3T3-E1 Cells

Two new phenyl glycosides, mangliesides A and B (1, 2), a new ionol glycoside, manglieside C (3), two new lignan glycosides, mangliesides D and E (4, 5), were isolated from the leaves of Manglietia phuthoensis, along with two known lignans, 3-methoxymagnolol (6) and obovatol (7). Their structures were established by means of 1D and 2D NMR, electrospray ionization (ESI)-MS and HR-ESI-MS experiments. Among them, compounds 2 and 5 significantly (p＜0.05) increased the growth and differentiation of osteoblastic MC3T3-E1 cells in vitro. Osteoporosis is characterized by a reduced bone mass, which results in increased bone fragility and fracture risk. Many osteoporotic patients have already lost a substantial amount of bone；therefore, a method of increasing bone mass by stimulating new bone formation is required. Bone is composed of mineralized organic matrix and bone cells. Osteoblasts are the active mature bone cells that synthesize the organic matrix and regulate its mineralization.