“…On the other hand, transient activation of p38 kinase in osteoblasts has been reported to be induced by cyclic stretch (Kusumi et al 2005), compression (Maeda et al 2007), fluid shear stress (Lee et al 2008;Yeh et al 2010), and magnetic force (Yuge et al 2003). Recent reports indicated that p38 activation is essential for Opg expression induced by cyclic stretch (Kusumi et al 2005), and compression-induce IL-8 expression (Maeda et al 2007). Intriguingly, acceleration of osteoblast differentiation induced by magnetic force is mainly attributed to p38 kinase activation, while the activity of ERKs or JNKs is dispensable (Yuge et al 2003).…”