Sphingolipidomics: high-throughput, structure-specific, and quantitative analysis of sphingolipids by liquid chromatography tandem mass spectrometry.
Sphingolipids are a highly diverse category of compounds that serve not only as components of biologic structures but also as regulators of numerous cell functions. Because so many of the sphingolipids in a biological system are bioactive and are often closely related structurally and metabolically (for example, complex sphingolipids<-->ceramide<-->sphingosine<-->sphingosine 1-phosphate), to understand the role(s) of sphingolipids in a given context one must conduct a "sphingolipidomic" analysis-i.e., a structure-specific and quantitative measurement of all of these compounds, or at least all members of a critical subset. Liquid chromatography tandem mass spectrometry (LC MS/MS) is currently the only technology with the requisite structural specificity, sensitivity, quantitative precision, and relatively high-throughput capabilities for such analyses in small samples ( approximately 10(6) cells). This review describes a series of protocols that have been developed for the relatively rapid analysis of all of the molecular species from 3-ketosphinganines through sphingomyelins and some glycosphingolipids (including all the compounds that are presently regarded as sphingolipid "second messengers") using normal- and reverse-phase LC to separate isometric and isobaric species (such as glucosylceramides and galactosylceramides) in combination with triple quadrupole (for MS/MS) and hybrid quadrupole-ion trap (for MS3) mass spectrometry. Also discussed are some of the issues remaining to be resolved in the analysis of the full sphingolipidome.
Merrill
Alfred H
AH
School of Biology, Georgia Institute of Technology, Atlanta, GA 30332-0230, USA. al.merrill@biology.gatech.edu
Sullards
M Cameron
MC
Allegood
Jeremy C
JC
Kelly
Samuel
S
Wang
Elaine
E
D000818:Animals; D002853:Chromatography, Liquid / Q000379:methods*; D006028:Glycosphingolipids / Q000737:chemistry; D006801:Humans; D008055:Lipids / Q000737:chemistry; D013058:Mass Spectrometry / Q000379:methods*; D008956:Models, Chemical; D021241:Spectrometry, Mass, Electrospray Ionization; D013107:Sphingolipids / Q000737:chemistry*; D013109:Sphingomyelins / Q000737:chemistry; D013110:Sphingosine / Q000031:analogs & derivatives / Q000737:chemistry; D013997:Time Factors
D006028:Glycosphingolipids; D008055:Lipids; D013107:Sphingolipids; D013109:Sphingomyelins; C002882:ketodihydrosphingosine; D013110:Sphingosine