Pregnane X receptor regulates bone homeostasis

Pregnane X receptor (PXR), the murine ortholog of the steroid and xenobiotic receptor (SXR), is a xenobiotic sensor which also plays a role in bone homeostasis. Azuma and colleagues analysed PXR knockout mice using dual-energy X-ray absorptiometry, quantitative micro-computed tomography and bone histomorphometry. Results showed a decreased bone mineral density and bone mass in knock out mice, resulting in increased mechanical fragility of bone. However, no changes in serum calcium and inorganic phosphate concentrations were seen, indicating mice were not hypophosphatemic. The reduced bone formation and increased bone resorption observed showed PXR knock out mice are osteopenic, highlighting PXR as a potential therapeutic target once the precise role of PXR signalling in bone is understood. Read the full article in Azuma et al. (2010) Journal of Endocrinology 207 257–263

DOI: 10.1677/JOE-10-0208