About the structure and biological function of dhCer
Structure. Dihydroceramides (N-acyl-sphinganines, or dhCer) belong to the group of ceramide lipids within the sphingolipids. Their structure consists of a sphingoid base, specifically dihydrosphingosine, and a fatty acid. The fatty acid can be of variable length, hydroxylated, and contain double bonds.
Function. In animals, dihydroceramides are primarily synthesized in the endoplasmic reticulum, and may then serve as biosynthetic precursor to ceramides. In comparison to ceramides, the absence of the double bond in the sphingoid base of dihydroceramides affects the biophysical properties of membranes rich in dhCer. They are linked to the production of reactive oxygen species in mitochondria, inducing and rectifying apoptosis, and accumulation of dhCer in the nervous system can lead to neuronal dysfunction.