Journal of Lipid Research (Mar 1968)
Changes in the fatty acid composition of cerebrosides and sulfatides of human nervous tissue with age
Abstract
Sphingogalactolipids (galactocerebrosides and sulfatides) have been isolated in almost quantitative yields from normal human nervous tissue (mostly brain) at different ages and their fatty acid compositions have been determined by gas-liquid chromatography.The ratio of hydroxy acids to normal acids increased slightly during myelination and then remained rather constant; in adults the ratio for cerebrosides was about 2, and for sulfatides, 0.6-0.8. In adult nervous tissue the two predominant fatty acids of cerebrosides and sulfatides were the C24, monounsaturated and 2-hydroxy saturated acids. The infant brain galactolipids had (compared with child and adult) a lower percentage of C22-C26 fatty acids and a much lower percentage of monoenoic acids, both of normal and hydroxy acids. Low activities of fatty acid elongation and desaturation systems during myelination are inferred.Fatty acid changes with age were the same for cerebrosides and sulfatides but occurred later in the sulfatides, which supports the hypothesis that the cerebrosides are precursors of the sulfatides. The adult pattern of fatty acid composition with regard to degree of unsaturation and total percentage of C22-C26 acids was reached as early as at 2 yr of age, but the percentage of odd-numbered (C23 and C25) fatty acids continued to increase up to the age of 10-15 yr.The fatty acid composition of the galactolipids of peripheral nerves differed mainly in its lower percentages of C25 and C26 acids and higher percentages of C22 and C16 acids. This composition is thus intermediate between those of brain and of extraneural organs.
