Please use this identifier to cite or link to this item:
Scopus Web of Science® Altmetric
Type: Journal article
Title: Vitamin D action and regulation of bone remodeling: Suppression of osteoclastogenesis by the mature osteoblast
Author: Baldock, P.
Thomas, G.
Hodge, J.
Baker, S.
Dressel, U.
O'Loughlin, P.
Nicholson, G.
Briffa, K.
Eisman, J.
Gardiner, E.
Citation: Journal of Bone and Mineral Research, 2006; 21(10):1618-1626
Publisher: Amer Soc Bone & Mineral Res
Issue Date: 2006
ISSN: 0884-0431
Statement of
Paul A Baldock, Gethin P Thomas, Jason M Hodge, Sara UK Baker, Uwe Dressel, Peter D O’Loughlin, Geoffrey C Nicholson, Kathy H Briffa, John A Eisman, Edith M Gardiner
Abstract: <h4>Unlabelled</h4>Vitamin D acts through the immature osteoblast to stimulate osteoclastogenesis. Transgenic elevation of VDR in mature osteoblasts was found to inhibit osteoclastogenesis associated with an altered OPG response. This inhibition was confined to cancellous bone. This study indicates that vitamin D-mediated osteoclastogenesis is regulated locally by OPG production in the mature osteoblast.<h4>Introduction</h4>Vitamin D stimulates osteoclastogenesis acting through its nuclear receptor (VDR) in immature osteoblast/stromal cells. This mobilization of calcium stores does not occur in a random manner, with bone preferentially removed from cancellous bone. The process whereby the systemic, humoral regulator is targeted to a particular region of the skeleton is unclear.<h4>Materials and methods</h4>Bone resorption was assessed in mice with vitamin D receptor transgenically elevated in mature osteoblasts (OSVDR). Vitamin D-mediated osteoclastogenesis was examined in vitro using OSVDR osteoblasts and osteoblastic RANKL: osteoprotegerin (OPG) examined in vivo and in vitro after vitamin D treatment.<h4>Results</h4>Vitamin D-mediated osteoclastogenesis was reduced in OSVDR mice on chow and calcium-restricted diets, with effects confined to cancellous bone. OSVDR osteoblasts had a reduced capacity to support osteoclastogenesis in culture. The vitamin D-mediated reduction in OPG expression was reduced in OSVDR osteoblasts in vivo and in vitro, resulting in a reduced RANKL/OPG ratio in OSVDR compared with wildtype, after exposure to vitamin D.<h4>Conclusions</h4>Mature osteoblasts play an inhibitory role in bone resorption, with active vitamin D metabolites acting through the VDR to increase OPG. This inhibition is less active in cancellous bone, effectively targeting this region for resorption after the systemic release of activated vitamin D metabolites.
Keywords: vitamin D
mature osteoblast
Description: Copyright © 2006 by the American Society for Bone and Mineral Research
DOI: 10.1359/jbmr.060714
Published version:
Appears in Collections:Aurora harvest 6
Molecular and Biomedical Science publications

Files in This Item:
There are no files associated with this item.

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.