Nervous system glycosphingolipids

Gangliosides are a class of glycosphingolipid characterized by the presence of one or more sialic acid residues. They are located in the cell membranes, particularly in the plasma membrane, of almost all cell types. They are anchored in the membranes through their ceramide moiety and have the polar sugar-containing group in the extracytoplasmic side. They are particularly abundant in the nervous system where their expression pattern is modulated during development. 

Another group of the acidic glycosphingolipids are the sulfoglycosphingolipids (formerly called sulfatides ). This field is comprehensively reviewed in [6]. Most abundant in mammalian tissues is 3-0-sulfogalactosylceramide (O Fig. IS) which occurs, e. g., in human kidney, rat lung, and in the human central and peripheral nervous system. Also, lactosyl -sulfate ceramide is found in mammalian tissues, e. g., in human kidney and liver. Higher glycosylated molecules are present, e. g., in human kidney, and in the rat and human central and peripheral nervous systems. 

Glycosphingolipid Ganglioside Biosynthesis Catabolism Nervous system Endoplasmic reticulum Golgi Glycosyltransferase Glycosidase Lipid-storage disorder... 

Ogawa-Goto, K., Ohta, Y., Kubota, K., Funamoto, N., Abe, T., Taki, T., and Nagashima, K. (1993). Glycosphingolipids of human peripheral nervous system myelins isolated from cauda equina. J. Neurochem. 61 1398-1403. 

The exact local origin of the fatty acid component of the glycosphingolipids in the central nervous system is not known for certain. Palmitate and oleate can pass from the blood into the brain or may be synthesized in the cytoplasm of the brain cells. To produce the longer fatty acid chains, the fatty acid elongation system of the mitochondria, e.g., those of oligodendrocytes, may then convert palmitate to C18 to Gae fatty acids (Fig. 2). 

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