Scherer Max, Böttcher Alfred, Schmitz Gerd, Liebisch Gerhard
Institute of Clinical Chemistry and Laboratory Medicine, University of Regensburg, Germany.
Biochim Biophys Acta. 2011 Feb;1811(2):68-75. doi: 10.1016/j.bbalip.2010.11.003. Epub 2010 Nov 23.
Sphingolipids comprise bioactive molecules which are known to play important roles both as intracellular and extracellular signalling molecules. Here we used a previously developed hydrophilic interaction chromatography tandem mass spectrometry (HILIC-MS/MS) method to profile plasma sphingolipids. Method validation showed sufficient precision and sensitivity for application in large clinical studies. Sample stability testing demonstrated that immediate plasma separation is important to achieve reliable results. Analysis of plasma from 25 healthy blood donors revealed a comprehensive overview of free sphingoid base, sphingosylphosphorylcholine (SPC), hexosylceramide (HexCer), lactosylceramide (LacCer), and ceramide-1-phosphate (Cer1P) species level. Besides the major sphingoid base sphingosine (d18:1), we found d16:1 and d18:2 species in most of these lipid classes. Interestingly, pronounced differences were detected in the species profiles of HexCer and LacCer. Additionally, sphingolipids were quantified in lipoprotein fractions prepared by fast performance liquid chromatography (FPLC). HexCer and LacCer showed similar distributions with about 50% in LDL, 40% in HDL and less than 10% in the VLDL fraction. More than 90% of sphingoid base phosphates were found in HDL and albumin containing fractions. In summary, HILIC-MS/MS provides a valuable tool to profile minor sphingolipid species in plasma and in lipoprotein fractions. Comparing profiles from tissues or blood cells, these species profiles may help to address the origin of plasma sphingolipids.
鞘脂类包含生物活性分子，已知其作为细胞内和细胞外信号分子发挥重要作用。在此，我们使用先前开发的亲水作用色谱串联质谱法（HILIC-MS/MS）对血浆鞘脂类进行分析。方法验证表明该方法具有足够的精密度和灵敏度，可应用于大型临床研究。样品稳定性测试表明，立即进行血浆分离对于获得可靠结果很重要。对25名健康献血者的血浆分析揭示了游离鞘氨醇碱、鞘氨醇磷酸胆碱（SPC）、己糖神经酰胺（HexCer）、乳糖神经酰胺（LacCer）和神经酰胺-1-磷酸（Cer1P）种类水平的全面概况。除了主要的鞘氨醇碱鞘氨醇（d18:1）外，我们在大多数这些脂质类别中还发现了d16:1和d18:2种类。有趣的是，在HexCer和LacCer的种类谱中检测到明显差异。此外，通过快速高效液相色谱法（FPLC）制备的脂蛋白组分中的鞘脂类进行了定量分析。HexCer和LacCer显示出相似的分布，约50%在低密度脂蛋白（LDL）中，40%在高密度脂蛋白（HDL）中，极低密度脂蛋白（VLDL）组分中不到10%。超过90%的鞘氨醇碱磷酸盐存在于HDL和含白蛋白的组分中。总之，HILIC-MS/MS为分析血浆和脂蛋白组分中的微量鞘脂类提供了一种有价值的工具。比较来自组织或血细胞的谱图，这些种类谱可能有助于确定血浆鞘脂类的来源。
