Role of angiogenesis on bone formation.

Angiogenesis and bone formation are coupled during skeletal development and fracture healing. This relationship, although known for some time, has not been properly explored. Advances in the discovery of how angiogenesis is regulated in physiological processes like embryogenesis, endometrial regeneration and wound healing or in pathologies such as cancer have provided a deeper understanding of how angiogenic factors may interact with bone cells to improve bone formation and bone regeneration. The lack of oxygen (hypoxia) and the subsequent generation of angiogenic factors have been shown to be critical in the development of a regular skeleton and achieving successful bone regeneration and fracture healing. Given that vascular status is important for a proper bone homeostasis, defining the roles of osteoblasts, osteoclasts, endothelial cells and angiogenic factors and their interactions in bone is a key issue for the development of new strategies to manage bone pathologies and nonfused fractures.