| 内容提要: |
During development and growth, in order to build up the skeleton and finally achieve its shape and size, bone is removed from some sites and deposited at other sites; this process is called bone modeling. Once the skeleton has reached its mature size and structure, bone remodeling contributes to maintaining bone mass of adult skeleton by replacing old tissue by newly formed bone tissue in the same location. During a person’s life-time, bone continuously underdoes remodeling, which is associated with maintaining a dynamic balance between bone formation and bone resorption.
There are 3 types of bone cells mainly responsible for the bone remodeling process, including bone forming osteoblast, bone resorbing osteoclast, and mechanosensing osteocytes. Balance in formation and activity of these 3 types of bone cells is crucial for healthy bone. Moreover, in bone homeostasis, osteoblasts not only play an important role in bone formation by synthesizing multiple bone matrix proteins, but also contribute to osteoclast maturation by soluble factors and cognate interaction, which leads to bone resorption. Due to the fact that osteoblasts are the primary cell type contributing to the synthesis and mineralization of bone during both bone formation and bone remodeling, elucidating mechanisms of the regulation of osteoblast differentiation and activity is critical, not only for understanding bone physiology but also for designing effective bone therapeutics. |