Fast calcium wave inhibits excessive apoptosis during epithelial wound healing

Abstract : Successful wound closure is mainly the result of two cellular processes: migration and proliferation. Apoptosis has also been suggested to play a role in the mechanisms of wound healing. The fast calcium wave (FCW), triggered immediately after a wound is produced, has been proposed to be involved in determining healing responses in epithelia. We have explored the effects of the reversible inhibition of FCW on the apoptotic and proliferative responses of healing bovine corneal endothelial (BCE) cells in culture. The most important findings of this study are that caspase-dependent apoptosis occurs during the healing process, that the amount of apoptosis has a linear dependence on the migrated distance, and that FCW inhibition greatly increases the apoptotic index. We have further been able to establish that FCW plays a role in the control of cell proliferation during BCE wound healing. These results indicate that one of the main roles of the wave is to inhibit an excessive apoptotic response of the healing migrating cells. This property might represent a basic mechanism to allow sufficient migration and proliferation of the healing cells to assure proper restitution of the injured tissue.