Application Notes:
Sphingomyelin is found in mammalian cell membranes, especially in the membranes of the myelin sheath. It is the most
abundant sphingolipid in mammals and is thought to be found mostly in the exoplasmic leaflet of the membrane although
there is also evidence of a sphingomyelin pool in the inner leaflet of the membrane. It is involved in signal transduction and
apoptosis. An improper ratio of sphingomyelin to ceramide has been shown to be a factor in Niemann-Pick disease and
neonatal respiratory distress syndrome.1 However, the ratio of sphingomyelin to ceramide is different for different cell
types.2 Sphingomyelin is an important amphiphilic component when plasma lipoprotein pools expand in response to large
lipid loads or metabolic abnormalities.3 In contrast to ceramides, N-hexanoyl-sphingosylphosphorylcholine does not initiate
vesicle formation in cells.4 Sphingosylphosphorylcholine has been shown to induce intracellular calcium release while its
short chain analog, N-acetyl-sphingosylphosphoylcholine, requires a significantly higher concentration to initiate the same
level of response.5
References:
1. C. St Clair et al. “The probability of neonatal respiratory distress syndrome as a function of gestational age and lecithin/sphingomyelin ratio” Am J
Perinatol., Vol. 25(8) pp. 473-480, 2008,
2. J. Kilkus et al. “Differential regulation of sphingomyelin synthesis and catabolism in oligodendrocytes and neurons” J Neurochem. Vol. 106(4) pp. 1745-
1757, 2008
3. N. Duan RD. “Absorption and lipoprotein transport of sphingomyelin” J Lipid Res., Vol. 47(1) pp. 154-171, 2006
4. R. Li, E. Blanchette-Mackie, and S. Ladisch “Induction of Endocytic Vesicles by Exogenous C6-ceramide” Journal of Biological Chemistry, vol. 274 pp.
21121-21127, 1999
5. D. Yule et al. “Sphingosine Metabolism Induces Ca2+ Oscillations in Rat Pancreatic Acinar Cells” The Journal of Biological Chemistry, Vol. 268(17) pp.
12353-12358, 1993