21. Although PLC prefers to act on phosphatidylcholine, it also shows weak catalytic activity with sphingomyelin and phosphatidylinositol. 22. In the intestinal tract cholesterol and sphingomyelin are co-exiting in lipid vesicles, liposomes and micelles. 23. The structure of sphingomyelin was first reported in 1927 as N-acyl-sphingosine-1-phosphorylcholine. 24. Sphingomyelin with set chain length, such as palmitoylsphingomyelin with a saturated 16 acyl chain, is available commercially.25. In this case, a fatty molecule, sphingomyelin , accumulates because patients lack an enzyme needed to degrade it. 26. Sphingomyelin obtained from natural sources, such as eggs or bovine brain, contains fatty acids of various chain length.27. It occurs in many lipid mixtures combining cholesterol with a phospholipid and / or sphingolipids e . g . sphingomyelin . 28. Fluoxetine has been shown to inhibit acid sphingomyelinase, a key regulator of ceramide levels which derives ceramide from sphingomyelin . 29. It is also understandable that considerable amount of dietary sphingomyelin is delivered into the colon and excreted in the feces. 30. One category termed a glycerophospholipid and the other a sphingomyelin , or more specifically within the sphingomyelin class, a sphingophospholipid.
