Single Bout Short Duration Fluid Shear Stress Induces Osteogenic Differentiation of MC3T3-E1 Cells via Integrin β1 and BMP2 Signaling Cross-Talk

Abstract

Fluid shear stress plays an important role in bone osteogenic differentiation. It is traditionally believed that pulsed and continuous stress load is more favorable for fracture recovery and bone homeostasis. However, according to our clinical practice, we notice that one single stress load is also sufficient to trigger osteogenic differentiation. In the present study, we subject osteoblast MC3T3-E1 cells to single bout short duration fluid shear stress by using a parallel plate flow system. The results show that 1 hour of fluid shear stress at 12 dyn/cm2 promotes terminal osteogenic differentiation, including rearrangement of F-actin stress fiber, up-regulation of osteogenic genes expression, elevation of alkaline phosphatase activity, secretion of type I collagen and osteoid nodule formation. Moreover, collaboration of BMP2 and integrin β1 pathways plays a significant role in such differentiation processes. Our findings provide further experimental evidence to support the notion that single bout short duration fluid shear stress can promote osteogenic differentiation.

Nanotopography Directs Mesenchymal Stem Cells to Osteoblast Lineage Through Regulation of microRNA-SMAD-BMP-2 Circuit

“…Some studies have presented evidences of collaboration between integrin and BMP‐2 signaling to induce osteoblast differentiation (Lai and Cheng, ; Mai et al, ). The inhibition of β1 integrin attenuates both synthesis and secretion of BMP‐2 as well as repression of BMP‐2 dowregulates β1 integrin gene expression in MC3T3‐E1 pre‐osteoblasts (Mai et al, ).…”

“…In addition, MC3T3-E1 cells cultured on Ti with nanotopography displayed an enhanced response to BMP-2 treatment compared with control Ti, suggesting that the BMP-2 signaling pathway was more effective on this surface. Some studies have presented evidences of collaboration between integrin and BMP-2 signaling to induce osteoblast differentiation (Lai and Cheng, 2005;Mai et al, 2013). The inhibition of b1 integrin attenuates both synthesis and secretion of BMP-2 as well as repression of BMP-2 dowregulates b1 integrin gene expression in MC3T3-E1 pre-osteoblasts (Mai et al, 2013).…”

Calcium response in bone cells at different osteogenic stages under unidirectional or oscillatory flow

“…3,4 Mechanical stimulation enhances the osteogenic differentiation of bone cells. [5][6][7][8] As an adaptive system, the bone incessantly remodels its structure in response to external chemical and physical stimuli, 9 and fluid flow is regarded as an essential mechanical stimulant for bone cells. 10 Three types of fluid flow are typically used in in vitro experiments of osteoblasts and osteocytes, that is, steady, pulsating, and oscillatory fluid flow.…”

Integrin-β1, not integrin-β5, mediates osteoblastic differentiation and ECM formation promoted by mechanical tensile strain

“…Integrin-β1 plays great roles in osteoblasts , activity, expression of an osteoblast-specific dominant negative form of integrin-β1 resulted in reduced bone mass [ 8 ]. Fluid flow shear stress increased integrin-β1 expression of osteoblasts [ 9 ], and the shear stress induced osteogenic differentiation through integrin-β1 [ 10 ].…”