About the structure and biological function of NdS
Structure. Non-hydroxy-fatty acid [N] dihydro-sphingosine [dS] ceramides (CER[NdS], or NdS) belong to the group of ceramide lipids within the sphingolipids. Their structure consists of a sphingoid base, specifically dihydrosphingosine, and a fatty acid, which is a non-hydroxy fatty acid. The fatty acid can be of variable length, hydroxylated, and contain double bonds.
Function. Non-hydroxy-dihydrosphingosines are mostly important to human skin where they serve structural and signaling roles. NdS ceramides are involved in the formation of the epidermal barrier to protect against the environment and prevent trans-epidermal water loss. Aberrations of skin ceramide levels can contribute or lead to skin conditions. Reduced levels of NdS ceramides are linked to psoriasis. Further, a fish-rich diet decreases NdS lipids in the liver but elevates them in the brain.