Sphingolipids, brain

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. 

Higher fatty acids such as lignoceric acid (24 0) and behenic acid (22 0) are found in high concentrations in brain sphingolipids. Finally, evidence exists for... 

J. S. O Brien and G. Rouser, The Fatty Acid Composition of Brain Sphingolipids Sphingomyelin, Ceramide, Cerebroside, and Cerebroside Sulfate, J. Lipid Res. 5, 339-342 (1964). 

The brain sphingolipids contain even-numbered, long-chain saturated and unsaturated fatty acids (Cig, C205 C22, C24). The long-chain fatty acids are probably synthesized by elongation of the saturated or unsaturated 16 (palmitic or palomitoleyl) or 18 (stearic or oleic) fatty acids. 

O Brien, J. S., and G. Rouser The fatty acid composition of brain sphingolipids sphingomyelin, ceramide, cerebroside and cerebroside sulfate. J. Lipid Res. 6, 339 (1964). 

C24 l(09 C24 1A15 Nervonic acid Found in brain sphingolipids... 

Gatt, S., 1963, Enzymatic hydrolysis of sphingolipids. 1. Hydrolysis and synthesis of ceramides by an enzyme from rat brain. J. Biol. Chem. 238 3131-3133. 

Hexoseamidase A is the enzyme which is deficient in Tay-Sachs disease. This inherited condition results in an accumulation of GM2 gangliosides (sphingolipids) in the brain. The consequences are mental retardation, paralysis, blindness and death by the age of 3-4 years. 

Sphingolipids were first described in a remarkable treatise on the chemical constitution of the brain by Johann L. W. Thudichum, a physician-scientist in London, who published his findings more than 100 years ago. A major impetus for the study of the chemistry and metabolism of the sphingolipids was the discovery of several rare human diseases that could be attributed to the abnormal accumulation of sphingolipids. This accumulation has been shown to result from a defect in catabolism that normally occurs in lysosomes. It is now known that many different kinds of sphingolipids exist, and more than 300 structures have been reported to occur in nature. 

Our new method of sphingolipid analysis using high performance liquid chromatography allows us to determine not only their quantities but also their homolog compositions in a small amount of tissue. We now feel that less than 1 mg of fresh brain or nerve tissue is sufficient for complete analysis. The application of this new method for analyzing cerebroside and sulfatide-in plaques of brain from a patient with multiple sclerosis has been recently described (15). 

Wang H, Post S, Woods A (2008) A minimalist approach to MALDI imaging of glycerophospholipids and sphingolipids in rat brain sections. Int J Mass Spectrom 278 143-149. doi 10. 1016/j.ijms.2008.04.005... 

Yavin, E., and Gatt, S., 1969, Enzymatic hydrolysis of sphingolipids. 8. Further purification and properties of rat brain ceramidase. Biochemistry 8 1692-1698. 

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