Ceramides are a family of lipid molecules that are made up of a sphingosine and a fatty acid. Ceramides are found in high concentrations within cell membranes.
Ceramides are one of the lipids of sphingomyelin, one of the major lipids in the lipid bilayer.
Ceramides act as a signaling molecules involving the regulation of cell differentiation, proliferation, and programmed cell death.
Ceramides are also found in the lipids of the skin and have a role in retaining water.
Ceramides are involved with water regulation because of their high capacity to prevent water loss.