Acid and neutral sphingomyelinases: roles and mechanisms of regulation

Biochem Cell Biol. 2004 Feb;82(1):27-44. doi: 10.1139/o03-091.


Ceramide, an emerging bioactive lipid and second messenger, is mainly generated by hydrolysis of sphingomyelin through the action of sphingomyelinases. At least two sphingomyelinases, neutral and acid sphingomyelinases, are activated in response to many extracellular stimuli. Despite extensive studies, the precise cellular function of each of these sphingomyelinases in sphingomyelin turnover and in the regulation of ceramide-mediated responses is not well understood. Therefore, it is essential to elucidate the factors and mechanisms that control the activation of acid and neutral sphingomyelinases to understand their the roles in cell regulation. This review will focus on the molecular mechanisms that regulate these enzymes in vivo and in vitro, especially the roles of oxidants (glutathione, peroxide, nitric oxide), proteins (saposin, caveolin 1, caspases), and lipids (diacylglycerol, arachidonic acid, and ceramide).

Publication types

  • Research Support, U.S. Gov't, P.H.S.
  • Review

MeSH terms

  • Animals
  • Ceramides / biosynthesis
  • Ceramides / physiology
  • Enzyme Inhibitors / pharmacology
  • HeLa Cells
  • Humans
  • Hydrogen-Ion Concentration
  • Hydrolysis
  • Ions / chemistry
  • Magnesium / chemistry
  • Proteins / metabolism
  • Second Messenger Systems / physiology
  • Sphingomyelin Phosphodiesterase / antagonists & inhibitors
  • Sphingomyelin Phosphodiesterase / metabolism*
  • Sphingomyelins / metabolism


  • Ceramides
  • Enzyme Inhibitors
  • Ions
  • Proteins
  • Sphingomyelins
  • Sphingomyelin Phosphodiesterase
  • Magnesium