Cortical bone formation involves several cross talks among Wnt, TGF-β, Ihh/PTHrP, and Notch signaling pathways.
Bone formation involves the distinct, but related processes of intramembranous ossification and endochondral ossification [ 1, 2].
Endochondral bone formation involves resorption of aggrecan-rich avascular cartilage, followed by deposition of mineral-rich vascularised bone.
Possible mechanisms of statins in bone formation involve stimulation of BMP-2 and endothelial nitric oxide synthase (eNOS) [ 13, 47- 50].
For example, the crosstalk between T cells and osteoblasts is known to be important in intermittent parathyroid hormone induced bone formation, involving Wnt signalling by Wnt10b [ 17], which we have previously shown to be GC-dependent in osteoblasts during development [ 18].
Two months after surgery, the AOC 14 + sheep showed large bone formations involving the lateral and medial osteotomy of the graft.
A multifactorial and multistep process of bone metastasis formation involves several biological mechanisms including angiogenesis, invasion through extracellular matrix degradation, osteoblast/osteoclast activation and bone remodeling activity (Guise and Mundy 1998).
OA is characterized by osteophyte formation reflecting new bone formation, which is associated mainly with subchondral bone sclerosis, together with progressive cartilage damage [ 22], whereas new bone formation in AS involves a complicated and multifactorial sequence generated from the initiating entheseal inflammation.
The formation of regenerate bone involves a sequence of events, including neoangiogenesis [29], chondrocyte differentiation with expression of bone matrix proteins [31], and collagen I formation [39].
Out of these factors, signaling by BMP is important in bone formation, which involves the ubiquitin proteasome pathway.
