Investigation of the Molecular Structure of the Human Stratum Corneum Ceramides [NP] and [EOS] by Mass Spectrometry.

Hinder, A.; Schmelzer, C.E.H.; Rawlings, A.V.; Neubert, R.H.H.

The aim of this study was to characterize the two ceramide (CER) subclasses CER[NP] and CER[EOS] of human stratum corneum and to identify the chemical structures of their subspecies. High-performance thin-layer chromatography and normal-phase high-performance liquid chromatography were used for the separation of CER fractions, whereas nanoelectrospray ionization tandem mass spectrometry was applied to investigate the chemical structures in detail. Thus, CER[EOS] fragmentation revealed that in addition to linoleic acid other esterified fatty acids occur in the ω-position. Of particular interest is the identification of a 17:2 fatty acid located in this part of the molecule. Several subspecies of CER[NP], including subspecies with odd numbers of carbon atoms in both chains, the non-α-hydroxylated fatty acid moiety (part N) and the phytosphingosine (part P), were identified. Furthermore, it was found that 12% of CER[NP] subspecies have an odd number of carbon atoms in both chains of the molecule. Similar results were obtained for CER[EOS]. Both the esterified fatty acid (part E) and the sphingosine base (part S) were found to contain odd-numbered chain lengths. These results underline the heterogeneity of the CER composition in the stratum corneum lipid bilayer. Copyright © 2011 S. Karger AG, Basel

CERAMIDES; GLYCOSPHINGOLIPIDS; MASS spectrometry; NUCLEAR spectroscopy; MOLECULAR structure

Skin Pharmacology & Physiology, 2011, Vol 24, Issue 3, p127

1660-5527

Academic Journal

10.1159/000322303