Figure 1.

Mechanical forces influence human physiology and pathophysiology.

Shear flow in blood vessel influences physiology and pathophysiology of endothelial cells and blood cells (adapted from Nakamura et al^[4]). Stretching of lung tissue regulates the synthesis of extracellular matrix^[16–17]. Exposure to microgravity is associated with atrophy in heart, muscle, and bone, which is also frequented in aging^[18–19]. Exercise-induced mechanical stimulus regulates gene expression for muscle fiber hypertrophy^[20–21]. Application of mechanical stress on periodontal ligament fibroblasts induces gene expression to regulate the development, differentiation, and maintenance of periodontal tissues^[22]. Hydrostatic or osmotic pressure promotes chondrogenesis of mesenchymal stem cells and the transition and differentiation of notochordal cells into nucleus pulposus cells in the intervertebral disc^[23–24].