sphingomyelin

The structure of sphingomyelin was first reported in 1927 as N-acyl-sphingosine-1-phosphorylcholine.

The daily intake of sphingomyelin for human with Western diet is about 300 mg.

The metabolism of sphingomyelin creates many products that play significant roles in the cell.

Under physiological conditions, only part of the sphingomyelin can be digested and absorbed.

Its been discovered that sphingomyelin plays a significant role in cell signaling pathways.

Similarly, sphingomyelin may be broken down by sphingomyelinase to form ceramide.

The outer-leaflet, facing the outside environment, contains phosphatidylcholine and sphingomyelin.

The function of sphingomyelin remained unclear until recently, when it was found to have a role in signal transduction.

Cholesterol absorption can be inhibited by supplementation of sphingomyelin in the diet.

Sphingomyelin breakdown is responsible for initiating many universal signaling pathways.

Other lipids, such as sphingomyelin, appear to be synthesised at the external leaflet.

Ceramide and sphingomyelin are important in some clinical disease:

Susceptible cells are subject to lysis of exposed sphingomyelin on their membrane surfaces.

The hydrophobic chains of sphingomyelin tend to be much more saturated than other phospholipids.

Likewise the degradation of sphingomyelin can produce ceramide which is involved in other signal pathways.

Sphingomyelin are also more prone to intermolecular hydrogen bonding than other phospholipids.

It also acts on sphingomyelin and phosphatidylinositol.

The ceramide is transported to the Golgi apparatus where it can be converted to sphingomyelin.

However, there is some evidence that there may also be a sphingomyelin pool in the inner leaflet of the membrane.

In this case, a fatty molecule, sphingomyelin, accumulates because patients lack an enzyme needed to degrade it.

Hydrolysis of sphingomyelin is catalyzed by the enzyme sphingomyelinase.

ENPP7 is the key enzyme in the gut that digests sphingomyelin.

Sphingomyelin can also increase the levels of ENPP7 after a long term of administration.

In the P. falciparum genome there is a single copy of a putative sphingomyelin synthase.

The intertwining hydrocarbon chains of sphingomyelin serve to strengthen the myelin sheath.