Study Of Osteoblastic Cells OPG/RANKL Expression Induced By Fluid Shear Stress Via ERK5Signalling Pathway

Objective:As China gradually into aging society, the elderly health problems become the focus of the whole society, osteoporosis becomes a public health problem due to its high incidence, at present the main methods of treat osteoporosis are drugs and movement, but the mechanism of bone feeling stress is not clear,because of this,doctors can’t tell patients clearly how to do exercise to promote health, this study used homemade Fluid shear stress (FSS) loading device to load physical strength Fluid shear stress on osteoblast (MC3T3-E1),to understand ERK5signaling pathway conduction mechanism, and osteoprotegerin,(OPG) and osteoclast differentiation factor (ODF), also known as nuclear factor kappa B predominate ligand receptor activation factor(RANKL) expression. And we can provide correctly theory for osteopenic disease.Methods:A specific inhibitor of ERK5(BIX02188)was used to inhibit the expression of ERK5mRNA. MTT assay and real-time PCR were used to investigate the cellular proliferation and ERK5/OPG/RANKL mRNA expression, respectively.Results:The expression of ERK5mRNA was effective inhabited by BIX02188at the concentration of15μmmol/L (P<0.05). After cultivating the MC3T3-E1with BIX02188, osteoblastic proliferation was significantly inhabited (P<0.05). Moreover, FSS significantly increased the expression of OPG mRNA (P<0.05) and reduced the expression of RANKL mRNACP<0.05). However, ERK5down-regulated OPG/RANKL mRNA expression induced by FSS (P<0.05).Conclusion: Physical strength of12dyne/cm2FSS can promote osteoblast proliferation,it can promote OPG mRNA expression and can inhibit RANKL mRNA expression; ERK5inhibitor (BIX02188) can significantly mediate the the expression of OPG/RANKL mRNA induced by fluid shear stress.