Changes in the Ceramide Composition of Rat Forebrain Gangliosides with Age

Abstract

Five major gangliosides (GM1, GD1a, GD1b, GT1b, and GQ1b) were extracted and isolated by normal-phase HPLC from the forebrain of Sprague-Dawley rats of ages ranging from 3 days to 24 months. Each ganglioside was fractionated by reverse-phase HPLC into the molecular species carrying a single long-chain base moiety. At all ages, the C18:1 and C20:1 long-chain base species predominated, whereas the C18:0 and C20:0 ones represented 1-3% of the total. The C18:1 long-chain base species, predominant at 3 days (91-96%), diminished with age and reached, at 2 years, 73%, 65%, 61%, 59%, and 45% of the total for GD1a, GM1, GT1b, GD1b, and GQ1b, respectively. The content of the C20:1 long-chain base species, low at birth (4-9%), increased with age in all gangliosides and reached, at 2 years, 27-55% of the total. The developmental behavior of the ganglioside species containing the C18:1 long-chain base was characterized by the following: (a) a biphasic profile with a maximum around 15 days for GD1a, the most abundant ganglioside at all ages; (b) an increase until 6 months for GM1; (c) a sharp decrease until 30 days, followed by leveling for GT1b; and (d) a low, constant level for GD1b and GQ1b. All the ganglioside species containing the C20:1 long-chain base showed a constant increase during development, the increase being more marked in the first 30 days.(ABSTRACT TRUNCATED AT 250 WORDS)

An Approach to Glycobiology from Glycolipidomics: Ganglioside Molecular Scanning in the Brains of Patients with Alzheimer’s Disease by TLC-Blot/Matrix Assisted Laser Desorption/Ionization-Time of Flight MS

“…Many papers have reported that the level of d20 : 1 sphingosine-containing ganglioside increases with age. [19][20][21][22][23] We also found that the levels of gangliosides with d20 : 1 sphingosine-containing molecular species were much higher than those of d18 : 1 sphingosine-containing ones in control patients and patients with Parkinson's disease. This change seems to be very specific to patients with Alzheimer's disease.…”

Dependence of rat liver CMP‐N‐acetylneuraminate:GM1 sialyltransferase (SAT IV) activity on the ceramide composition of GM1 ganglioside

“…In the present study, for the first time, the GDla-synthetase activity of SAT IV was studied on a number of GM1 ganglioside molecular species, differing in either LCB or fatty acid composition, generally representative of the variability normally encountered in vivo [2,3]. The enzyme source used for the study of SAT IV activity was a highly purified Golgi apparatus fraction prepared from rat liver.…”

“…In fact, long c!min bases (LCB) and fatty acids, ceramide components, may ~Lry in both length and unsaturation, yielding several molecuiar species [1,2]. Remarkable differences in the lipid composition are observed in extraneural tissues, including liver [3], aid, for a given tissue, also between gangliosides deriving flom distinct biosynthetic pathways (e.g.…”

“…Remarkable differences in the lipid composition are observed in extraneural tissues, including liver [3], aid, for a given tissue, also between gangliosides deriving flom distinct biosynthetic pathways (e.g. the so-called 'a' a ad 'b' series) [2]. Ganglioside biosynthesis proceeds through the sequential transfer of monosaccharide units from sugar n acleotide donors to appropriate sphingolipid acceptors, cataiyzed by specific glycosyltransferases [4].…”

Direct interaction, instrumental for signaling processes, between LacCer and Lyn in the lipid rafts of neutrophil-like cells

“…GSLs have been found to modulate cell signaling processes through specifi c interactions between their oligosaccharide chains and proteins/glycoproteins in their environment. In contrast, it is unclear whether ceramides play specifi c roles in such processes, although changes in the structures of both the long-chain base and the fatty acids have been associated with the differentiation and aging processes (35)(36)(37)(38). In addition, ceramides resulting from These results are similar to those observed when D-HL-60 cells were loaded with natural LacCer molecules containing very long and short/medium fatty acids, suggesting that the photoactivable LacCer derivatives mimic the natural molecules.…”