A rapid and quantitative LC-MS/MS method to profile sphingolipids.
Sphingolipids comprise a highly diverse and complex class of molecules that serve not only as structural components of membranes but also as signaling molecules. To understand the differential role of sphingolipids in a regulatory network, it is important to use specific and quantitative methods. We developed a novel LC-MS/MS method for the rapid, simultaneous quantification of sphingolipid metabolites, including sphingosine, sphinganine, phyto-sphingosine, di- and trimethyl-sphingosine, sphingosylphosphorylcholine, hexosylceramide, lactosylceramide, ceramide-1-phosphate, and dihydroceramide-1-phosphate. Appropriate internal standards (ISs) were added prior to lipid extraction. In contrast to most published methods based on reversed phase chromatography, we used hydrophilic interaction liquid chromatography and achieved good peak shapes, a short analysis time of 4.5 min, and, most importantly, coelution of analytes and their respective ISs. To avoid an overestimation of species concentrations, peak areas were corrected regarding isotopic overlap where necessary. Quantification was achieved by standard addition of naturally occurring sphingolipid species to the sample matrix. The method showed excellent precision, accuracy, detection limits, and robustness. As an example, sphingolipid species were quantified in fibroblasts treated with myriocin or sphingosine-kinase inhibitor. In summary, this method represents a valuable tool to evaluate the role of sphingolipids in the regulation of cell functions.
Institute for Clinical Chemistry and Laboratory Medicine, University of Regensburg, Regensburg, Germany.
Max
M
Scherer
Kerstin
K
Leuthäuser-Jaschinski
Josef
J
Ecker
Gerd
G
Schmitz
Gerhard
G
Liebisch
D000818:Animals; D002478:Cells, Cultured; D002853:Chromatography, Liquid / Q000379:methods*; D005229:Fatty Acids, Monounsaturated / Q000737:chemistry / Q000494:pharmacology; D005347:Fibroblasts / Q000737:chemistry / Q000166:cytology / Q000187:drug effects; D006801:Humans; D007166:Immunosuppressive Agents / Q000737:chemistry / Q000494:pharmacology; D015394:Molecular Structure; D013107:Sphingolipids / Q000032:analysis*; D053719:Tandem Mass Spectrometry / Q000379:methods*
D005229:Fatty Acids, Monounsaturated; D007166:Immunosuppressive Agents; D013107:Sphingolipids; C001996:thermozymocidin