Mechanobiology of osteoblast

Osteoblast (OB), a key constituent cell of bone tissue, is the main cell responsible for bone formation. Moreover, OBs are mechanosensitive and can respond to mechanical stimulation and convert physical signals into biochemical signals, which regulates gene expression and thus affects cellular function of osteoblasts. Research has demonstrated that OBs respond to both mechanical loading and mechanical unloading conditions. Mechanical loading conditions, such as fluid shear stress (FSS), vibration, stretch, and compression force, promote osteoblast proliferation and differentiation. Alternatively, mechanical unloading conditions, such as simulated microgravity via random positioning machine (RPM), exhibit inhibitory effects on osteoblast proliferation and differentiation. Various mechanosensitive molecules and signaling pathways are involved in the OB response to mechanical stimulation. In this chapter, we summarize the characteristics and function of OBs and discuss recent advances in the effects of various mechanical stimuli on OBs. Moreover, we examine the mechanotransduction mechanism of OBs.