Overstressed mechanical stretching activates survival and apoptotic signals in fibroblasts.

The interest of scientists in the effects of mechanical stresses on cells is growing, in order to reproduce and understand cell behaviour in an environment closely reproducing physiological conditions. There have been many studies showing that mechanical stimulations are involved in regulating the proliferation, apoptosis and synthesis of proteins and cell morphology. In this study, we have considered the effects of a 20% stretching mechanical stress on MRC5 lung fibroblast cells in order to verify the role of survival/apoptotic pathways. As a survival pathway, the activation of Akt has been studied in association with pro-apoptotic or anti-apoptotic signals such as the Bax/Bcl-2 ratio and cleavage of caspases 3 and 9. Findings have shown the effects of overstressed cellular stretching to be a balance of a cause-and-effect reaction between survival and apoptosis. Copyright 2010 S. Karger AG, Basel.