Six new resin derivatives from flowers of Humulus lupulus L. with anti-osteoporosis activities.

Six new resin derivatives, humuluslupulus A-F (1-6), were isolated from flowers of Humulus lupulus L., together with thirteen known compounds (7-19). The structures of isolated compounds were identified by IR, HRESIMS, NMR analysis, and compared with data from the literature. The anti-osteoporosis activities of compounds 1-6 were evaluated by MTT assay and Western blot analysis in osteoblasts. Among them, compounds 2, 3, 4, 6 could increase the osteoblastic proliferation. Compounds 1-6 could all improve the expressions of bone formation related proteins, including Runx2, OPN and BMP-2. It can be confirmed that new resin derivatives of hop have potentialities for promoting osteoblastic bone formation.