Sphingolipids nomenclature

FIGURE 3-3 Structure of some simple sphingolipids. X may be a complex polysaccharide either containing sialic acid (gangliosides) or not (globosides). See also Figures 3-4 and 3-9 for the nomenclature and structure of some of the complex brain sphingolipids. 

The polar character of the liposomal core makes the encapsulation of polar drug molecules possible. Amphiphilic and lipophilic molecules are solubilized within the phospholipid bilayer according to their affinity toward the phospholipids. Participation of nonionic surfactants instead of phospholipids in the bilayer formation results in Niosomes . The term sphingosomes is suggested for vesicles from sphingolipids. However, the nomenclature is not consistent, and the term liposomes is used as a general term, although vesicles would be the better choice. 

Some years ago, Celmer and Carter2 proposed a rational nomenclature for cerebrosides and phosphatides, but Klenk and coworkers3 kept the old names in grouping the zoo-sphingolipids, which were denoted as (a) cerebrosides, (b) sulfatides, and (c) gangliosides. 

On a practical level, the sphingolipid field is caught somewhat awkwardly between old and new nomenclatures due to differences in the information that one gets from traditional analytical methods such as radiolabeling followed by thin-layer chromatography versus more structure-specific methods such as mass spectrometry (MS). 

The nomenclature of polar lipids is often confusing. In this chapter polar lipids with glycerol as the molecular backbone are referred to as phospholipids, and those derived from sphingosine - sphingolipids, and all lipids linked to any type of carbohydrate moiety - as glycolipids. Thus, in this chapter the term polar lipids refers to phospholipids, sphingolipids and glycolipids. 

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