Cerebrospinal fluid sphingolipid and sterol metabolite profiles of neurologically normal subjects

Although glycosphingolipids (GSLs) and sterol metabolites are known to be involved in many diseases, including neurodegenerative disorders, the quantification of these molecules in humans has been scarcely investigated. Similarly, the effects of age, sex, and statin use have not been sufficiently investigated or reported in the literature. In this study, we measured the levels of human cerebrospinal fluid (CSF) GSLs of various fatty acid acyl chain lengths and sterol metabolites using hydrophilic interaction liquid chromatography and electrospray tandem mass spectrometry in a neurologically normal population. We successfully quantified the presence of glucosylated cholesterol, galactosylated cholesterol, glucosylated sitosterol, glucosylceramide (GlcCer), galactosylceramide, lactosylceramide (LacCer), and galabiosylceramide (Gb2). There were no statistically significant differences in CSF concentrations of these lipids between males and females. We also found no correlation between CSF concentration and age or statin dose, except for GlcCer d18:1-C23:1. Significant positive correlations with age were shown only in males. Our results indicate that, in future studies, age and sex should be taken into consideration when comparing CSF GSL levels in patients with neurological disorders with those in neurologically normal control subjects.