Osteocyte cell density is reduced during vitamin D depletion and predicts osteoclast surface and bone mineral volume

Although the association between hip fracture risk and vitamin D deficiency is well established, understanding of the cellular mechanisms is less clear. Previously, we have reported maintaining adequate levels of serum 25-hydroxyvitamin D (25D) prevent bone loss by reducing RANKL-mediated osteoclastic bone resorption in an animal model. Interestingly, it has been demonstrated that increased bone resorption is mediated by osteocytes (OCY) either via apoptosis or trans-cellular signalling. Hence, we have used our vitamin D-deplete animal model to investigate the relationship between trabecular bone OCY cell density and other bone variables.