Lipid composition of myelin in multiple sclerosis

Abstract

Myelin was isolated from histologically normal white matter and plaques from MS patients and from white matter of neurologically normal controls. No difference was found in the total lipid content. There were no detectable deficits in MS myelin of phosphoglycerides, plasmalogens or sphingolipids. Gangliosides and lysolecithin were not detected. Analysis of the fatty aldehyde composition of the phosphoglycerides and the fatty acid composition of the cholesteryl esters, phosphoglycerides and sphingolipids did not show any differences between the normal and MS myelin.

Water content and myelin water fraction in multiple sclerosis

“…The observed decrease in myelin signal is supported by histopathological studies that found demyelination [1] as well as decreased myelin-associated glycoprotein immunostaining in white matter that appeared normal with luxol fast blue [24].An early study suggested that since myelin is rich in lipid, and makes up the majority of all lipid found in white matter, total lipid determination could be used as a simple indicator for myelin [47]. It was found that NAWM showed a 15.5 % reduction in total lipid when compared with control white matter,suggesting a similar decrease in NAWM myelin.Several other studies have examined galactolipids, including cerebrosides, which are thought to be more directly related to myelin content and have found galactolipid decreases in NAWM of 13.5 % [4] and 17 % [17] when compared with control white matter. The reduction in these biochemical markers of myelin has, in the past, been attributed to the inclusion of small plaques in the NAWM assayed [44].MRI data,such as the present study, would suggest that such findings might also be due to a more diffuse reduction of non-lesional myelin in NAWM.This diffuse myelin loss could be due to concomitant loss of axons in Wallerian degeneration as reported in NAWM [14,15].…”

Myelin Recovery in Multiple Sclerosis: The Challenge of Remyelination

“…The lipids are assembled concomitantly with myelin-specific membrane proteins, the most abundant being the intrinsic (integral) membrane protein—myelin proteolipid protein (PLP) and the extrinsic (peripheral) myelin basic protein (MBP) while myelin-associated glycoprotein (MAG), myelin oligodendrocyte glycoprotein (MOG), and 2′3′-cyclic-nucleotide 3′-phosphodiesterase (CNP) are quantitatively minor constituents (Figure 1B). The three main classes of lipids comprising CNS myelin are cholesterol, glycosphingolipids (derivatives of galactosylceramides (GalCer) and glucosylceramides (GlcCer)), and phospholipids (PLs): these myelin lipid classes have long been known to have constant molar proportions of 2:1:2 [10,11]. …”

Is the myelin membrane abnormal in multiple sclerosis?

“…The cholesterol content is similar in both, and no cholesterol esters have been detected [37,45]. However, normal levels [36,74] have been reported by some investigators. However, normal levels [36,74] have been reported by some investigators.…”