Role Of P38MAPK Signaling Pathways In The Apoptosis Of C2C12 Myoblast Cells Subjected To Cyclical Stretch

Aim External pterygoid muscle plays an important role in the development of dent facial deformity. It can be adapted to the stimuli of the environment. The reconstruction of external pterygoid muscle is indispensable by cellular proliferation, differentiation and apoptosis. Successful constructs muscle cells in vitro mechanical stimulation models based on research on its P38MAPK signaling pathways of apoptosis function.Methodology The cells were divided in control group and SB203580 treatment group. Cyclic tensile stress was applied on the C2C12 myoblast cells for Oh,6h,12h and 24h in each group. The cells were given a multichannel cell tensile stress loader. The stretch cells's value group is 15%, 10cycle/min. And that was to say each cycle including 3-s stretch/3-s relaxation. Hoechst 33258 fluorescent staining and optical microscope were used to detect cell apoptosis. Hoechst 33258 fluorescent staining and optical microscope were used to detect cell apoptosis. RT-PCR, flow cytometric analysis were used to observe the apoptosis of C2C12 myoblast cell and Western blotting were used to detect the activity of P38MAPK and phosphor-p38MAPK. We used SPSS 17.0 Statistical Package to analyze the data.Result The optical microscope tested the change in the morphology. Hoechst 33258 staining showed that after treatment with cyclic stress, the cell took the typical appearance of apoptosis with chromatin condensation and apoptotic bodies. RT-PCR and flow cytometric showed that with the extension of time the rate of the apoptosis of C2C12 myoblast cell was increased (P<0.05). the results showed that the apoptosis was markedly affected after we used the SB203580 before imposing cyclical tensile stress, and the phosphor-p38MAPK expression declined apparently (P<0.05). Conclusion1. Periodical stretching could induce the cell apoptosis.2. The expression of P38MAPK and phosphor-p38MAPK protein was lowest after 6h later the cyclic streth and it was increasing with the time longer.3. The SB203580 in tervention was able to remarkably reduce the apoptosis of the cells, and also effectively suppress the P38MAPK protein and p-p38MAPK protein expression.4. These findings demonstrate that, P38MAPK signaling pathways in stress mediated into C2C12 myoblast cell apoptosis plays an important role.