Estrogen Receptor α (ERα) and Estrogen Related Receptor α (ERRα) are both transcriptional regulators of the Runx2-I isoform.

Runx2 is a master regulator of bone development and has also been described as an oncogene. Estrogen Receptor α (ERα) and Estrogen Related Receptor α (ERRα), both implicated in bone metabolism and breast cancer, have been shown to share common transcriptional targets. Here, we show that ERα is a positive regulator of Runx2-I transcription.

Follicle-stimulating hormone does not impact male bone mass in vivo or human male osteoclasts in vitro.

Bone loss in the elderly is mainly caused by osteoclast-induced bone resorption thought to be causally linked to the decline in estrogen and testosterone levels in females and males. Recently, involvement of follicle stimulating-hormone (FSH) in this process has been suggested to explain in part the etiology of the disease in females, whereas its role in males has never been examined. In this study, the direct impact of FSH on bone mass of 16-week-old C57BL/6J male mice by either daily intermittent application of 6 or 60 mug/kg of FSH or continuous delivery via miniosmotic pump of a dose of 6 mug/kg over the course of a month was assessed.

Highly potent geminal bisphosphonates. From pamidronate disodium (Aredia) to zoledronic acid (Zometa).

Bisphosphonates (BPs) are pyrophosphate analogues in which the oxygen in P-O-P has been replaced by a carbon, resulting in a metabolically stable P-C-P structure. Pamidronate (1b, Novartis), a second-generation BP, was the starting point for extensive SAR studies. Small changes of the structure of pamidronate lead to marked improvements of the inhibition of osteoclastic resorption potency.