Ceramide

Parallel to the alteration of the cell redox status, we observed the accumulation of ceramide, and this increase was inhibited substantially by the exogenous addition of GSH.

Therefore, our results suggest that the accumulation of ceramide is an event that lies downstream from ROS generation. The long term accumulation of ceramide might result from increased de novo synthesis via activation of ceramide synthase or from sphingomyelin breakdown by acidic or neutral sphingomyelinases.

In our H2O2-treated PC12 cells, fumonisin B1, a specific inhibitor of ceramide synthase, did not significantly reduce the ceramide levels observed within the time frame of these assays. On the other hand, the addition of GSH prevented H2O2-induced accumulation of ceramide. (R1)