Is synthesis of sphingosine essential for oxidative stress-induced apoptosis of photoreceptors?
These results suggest that oxidative stress enhances formation of ceramide and its subsequent breakdown to Sph; ceramide and/or Sph would then trigger photoreceptor apoptosis. Preventing Sph synthesis or promoting its phosphorylation to S1P rescued photoreceptors, suggesting that Sph is a mediator of their apoptosis and modulation of Sph metabolism may be crucial for promoting photoreceptor survival.
NO can deregulate free radicals balance resulted in genotoxic effect, posttranslational modification of repair enzymes and thus coordinated development of genomic instability and increase of cancer risk.