ABSTRACT
Cerebrosides, including glucosylceramides (GlcCers) and galactosylceramides (GalCers), are important membrane components of animal cells with deficiencies resulting in devastating lysosomal storage disorders. Their quantification is essential for disease diagnosis and a better understanding of disease mechanisms. The simultaneous quantification of GlcCer and GalCer isomers is, however, particularly challenging due to their virtually identical structures. To address this challenge, we developed a new LC/MS-based method using differential ion mobility spectrometry (DMS) capable of rapidly and reproducibly separating and quantifying isomeric cerebrosides in a single run. We show that this LC/ESI/DMS/MS/MS method exhibits robust quantitative performance within an analyte concentration range of 2.8-355 nM. We further report the simultaneous quantification of nine GlcCers (16:0, 18:0, 20:0, 22:0, 23:0, 24:1, 24:0, 25:0, and 26:0) and five GalCers (16:0, 22:0, 23:0, 24:1, and 24:0) molecular species in human plasma, as well as six GalCers (18:0, 22:0, 23:0, 24:1, 24:0 and 25:0) and two GlcCers (24:1 and 24:0) in human cerebrospinal fluid. Our method expands the potential of DMS technology in the field of glycosphingolipid analysis for both biomarker discovery and drug screening by enabling the unambiguous assignment and quantification of cerebroside lipid species in biological samples.
Subject(s)
Cerebrosides/chemistry , Cerebrosides/isolation & purification , Chromatography, Liquid/methods , Ion Mobility Spectrometry/methods , Spectrometry, Mass, Electrospray Ionization/methods , Tandem Mass Spectrometry/methods , Cerebrosides/blood , Cerebrosides/cerebrospinal fluid , Chromatography, Liquid/standards , Female , Humans , Ion Mobility Spectrometry/standards , Isomerism , Middle Aged , Reference Standards , Spectrometry, Mass, Electrospray Ionization/standards , Tandem Mass Spectrometry/standards , Time FactorsABSTRACT
A molecule isolated from the cerebrospinal fluid of sleep-deprived cats has been chemically characterized and identified as cis-9,10-octadecenoamide. Other fatty acid primary amides in addition to cis-9,10-octadecenoamide were identified as natural constituents of the cerebrospinal fluid of cat, rat, and human, indicating that these compounds compose a distinct family of brain lipids. Synthetic cis-9,10-octadecenoamide induced physiological sleep when injected into rats. Together, these results suggest that fatty acid primary amides may represent a previously unrecognized class of biological signaling molecules.
Subject(s)
Brain Chemistry , Cerebrosides/cerebrospinal fluid , Lipids/cerebrospinal fluid , Oleic Acids/cerebrospinal fluid , Sleep , Animals , Cats , Cerebrosides/chemistry , Cerebrosides/pharmacology , Humans , Lipids/chemistry , Lipids/pharmacology , Magnetic Resonance Spectroscopy , Mass Spectrometry , Molecular Weight , Oleic Acids/chemistry , Oleic Acids/pharmacology , Rats , Signal Transduction , Sleep/drug effects , Spectrometry, Mass, Fast Atom Bombardment , Spectrophotometry, InfraredABSTRACT
The author reports of the achieved results in a quantitative study of general lipids, phospholipids and cerebrosides in the CSF of 37 patients with demyelinating diseases, of 11 patients with vascular brain pathology and 7 with Van Bogart's panencephalitis. The control group consisted of 14 patients without focal lesions of the nervous system, with normal CSF indices. In demyelinating diseases there was a significant increase in the content of kephalines and cerebrosides. In Van Bogart's panencephalitis there was a much higher increase of kephalines, general lipids and phospholipids. In vascular brain disorders there was a moderate increase of all lipids. The possible pathochemical mechanisms of the depicted changes in the content of the lipids in the CSF are discussed.
Subject(s)
Demyelinating Diseases/cerebrospinal fluid , Lipids/cerebrospinal fluid , Adolescent , Adult , Cerebrosides/cerebrospinal fluid , Cerebrospinal Fluid Proteins/cerebrospinal fluid , Cerebrovascular Disorders/cerebrospinal fluid , Diffuse Cerebral Sclerosis of Schilder/cerebrospinal fluid , Female , Humans , Male , Middle Aged , Multiple Sclerosis/cerebrospinal fluid , Phosphatidylethanolamines/cerebrospinal fluid , Phospholipids/cerebrospinal fluid , Subacute Sclerosing Panencephalitis/cerebrospinal fluidSubject(s)
Lipids/cerebrospinal fluid , Microchemistry , Amyotrophic Lateral Sclerosis/cerebrospinal fluid , Cerebrosides/cerebrospinal fluid , Cholesterol/cerebrospinal fluid , Chromatography, Thin Layer , Evaluation Studies as Topic , Fatty Acids, Nonesterified/cerebrospinal fluid , Humans , Hydrocarbons/cerebrospinal fluid , Methods , Phospholipids/cerebrospinal fluid , Triglycerides/cerebrospinal fluidSubject(s)
Brain Neoplasms/cerebrospinal fluid , Glycolipids/cerebrospinal fluid , Neoplasm Metastasis/cerebrospinal fluid , Phospholipids/cerebrospinal fluid , Breast Neoplasms/cerebrospinal fluid , Cerebrosides/cerebrospinal fluid , Chromatography, Thin Layer , Gangliosides/cerebrospinal fluid , Humans , Lung Neoplasms/cerebrospinal fluid , Methods , Phosphatidylethanolamines/cerebrospinal fluid , Spinal PunctureABSTRACT
A technique was developed to isolate sufficient material for compositional analysis of cerebroside from pooled human cerebrospinal fluid. The carbohydrate moiety was principally galactose. The sphingosine base and fatty acid compositions were found to be similar to that of brain cerebroside. The presence of a contaminant in commercial silica gel which chromatographed like the trimethylsilyl derivative of glucose is described.
