The Number of Cyclic Stretch Regulates Cellular Elasticity in C2C12 Myoblasts

Kenji Takemoto, Takeomi Mizutani, Kazushi Tamura, Kazuki Takeda, Hisashi Haga, Kazushige Kawabata

Faculty of Advanced Life Sciences, Hokkaido University, Sapporo, Japan.

DOI: 10.4236/cellbio.2012.11001                

Abstract

Mechanical stimulations have been shown to regulate cellular mechanical properties. However, the stimulation patterns for effective regulation are as yet unclear. We investigated the effects of application of differing numbers of mechanical stimulation sets, each set consisting of 8% extension and compression to cells via deformation of cell culture elastic chamber, on cellular elasticity. Elasticity increased with only a single step-like stretch and with a single step-like stretch after 1 set of mechanical stimulation, whereas elasticity did not change with a single step-like stretch after 10 sets of mechanical stimulation. These results indicate that the increase in cellular elasticity with the single step-like stretch depends on the number of applied mechanical stimulations. Immunofluorescence staining showed that phosphorylation and dephosphorylation of myosin regulatory light chain (MRLC), which regulates intracellular contractile force and cellular elasticity, accompanied cellular elasticity changes. These findings suggest that cellular elasticity changes under cyclic and step-like stretches are mediated by MRLC.

Keywords

Cellular Elasticity; Mechanical Stimulation; Atomic Force Microscopy; Myosin Regulatory Light Chain; Regulation of Cellular Function

Conflicts of Interest

The authors declare no conflicts of interest.

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