Ceramide signaling in retinal degeneration.

Retinal degenerations (RD) are a complex heterogeneous group of diseases in which retinal photoreceptors and the supporting retinal pigment epithelial cells die irreversibly, causing visual loss for millions of people. Mutations on more than 150 genes have been discovered for RD and there are many forms that possess complex etiology involving more than one gene and environmental effect. For years many have searched for some common intracellular second messenger for these many forms of cell death which could be targeted for therapy. Ceramide is a novel cellular second messenger which signals for apoptosis. Several lines of evidence suggest an integral role of ceramide in photoreceptor apoptosis and cell death. Understanding their role in the pathogenic pathways of retinal degenerative diseases is important for development of targeted therapeutics.