Magnolol prevents ovariectomy‑induced bone loss by suppressing osteoclastogenesis via inhibition of the nuclear factor‑κB and mitogen‑activated protein kinase pathways.

Magnolol is the active component of the traditional Chinese medicine Magnolia officinalis, and has antioxidant, anti‑inflammatory and anticancer activities, as well as an effect on bone metabolism in vitro. In the present study, it is reported that magnolol suppresses osteoclastogenesis in vivo and in vitro. Magnolol prevented ovariectomy‑induced bone loss and osteoclastogenesis in vivo, and decreased the serum levels of C‑terminal telopeptide of type 1 collagen, interleukin‑6, tumor necrosis factor (TNF)‑α and tartrate‑resistant acid phosphatase 5B.

[Expression and regulation of the SOST gene].

Sclerostin(SOST), mainly expressed in osteocytes, is a negative regulator of bone formation. Hormones PTH and E2 inhibit the expression of the SOST gene. Transcription factors Osterix, Runx2, and Mef2c promote the SOST expression, while Sirt1 negatively regulates the SOST expression.