The effects of MAPK inhibitors on a proteasome inhibitor, MG132-induced HeLa cell death in relation to reactive oxygen species and glutathione.

MG132 as a proteasome inhibitor can induce apoptotic cell death through formation of reactive oxygen species (ROS). In this study, we investigated the effects of MAPK (MEK, JNK or p38) inhibitors on MG132-induced HeLa cell death in relation to ROS and glutathione (GSH). MG132-induced cell growth inhibition and apoptosis in HeLa cells, which was accompanied by the loss of mitochondrial membrane potential (MMP; DeltaPsi(m)). MG132 increased ROS level including O(2)(*-) and GSH depleted cell number in HeLa cells. All the MAPK inhibitors slightly enhanced the cell growth inhibition but did not intensify apoptosis in MG132-treated HeLa cells. Each MAPK inhibitor differentially changed the levels of ROS and GSH content in MG132-treated cells. In conclusion, MAPK inhibitors partially influence apoptosis, ROS and GSH levels in MG132-treated HeLa cells. 2009 Elsevier Ireland Ltd. All rights reserved.