Sphingomyelins
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 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. Sphingomyelin is an important amphiphilic component when plasma lipoprotein pools expand in response to large lipid loads or metabolic abnormalities1. Sphingomyelin is also involved in signal transduction and apoptosis.2 An improper ratio of sphingomyelin to ceramide has been shown to be a factor in Niemann-Pick disease3 and neonatal respiratory distress syndrome.4
References:
- N. Duan RD. “Absorption and lipoprotein transport of sphingomyelin” J Lipid Res., Vol. 47(1) pp. 154-171, 2006
- R. N. Kolesnick, A. Haimovitz-Friedman, Z. Fuks “The sphingomyelin signal transduction pathway mediates apoptosis for tumor necrosis factor, Fas, and ionizing radiation” Biochem Cell Biol., Vol. 72(11-12) pp. 471-474, 1994
- M. Schmuth, et al. “Permeability barrier disorder in Niemann-Pick disease: sphingomyelin-ceramide processing required for normal barrier homeostasis” J Invest Dermatol., Vol. 115(3) pp. 459-466, 2000
- 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