Deficiencies of polyunsaturated fatty acids and replacement by nonessential fatty acids in plasma lipids in multiple sclerosis.

Abstract

Fatty acid compositions of plasma phospholipids, cholesteryl esters, triacylglycerols, and nonesterifiled fatty acids of 14 clinically proven and graded cases of multiple sclerosis were determined by capillary gas chromatography and compared with the values obtained for 100 normal, healthy subjects. In phospholipids, linoleic acid (18:2to6; 18 carbon atoms, 2 double bonds, 6 carbon atoms beyond last double bond) was normal and 18:3w6 was increased, but all subsequent w6 acids were subnormal (P < 0.001), indicating impairment of chain elongation. All W3 acids were subnormal. The paucity of polyunsaturated fatty acids was compensated mass-wise by an increase in saturated acids. Disproportionate increases in short-chain, saturated, and monounsaturated acids, decreases in long-chain homologs, and increases of branched and odd-chain acids were observed. Loss of polyunsaturated fatty acids and replacement by nonessential acids lowered mean chain length and raised mean melting point significantly, suggesting that lowered membrane fluidity was only partially compensated by endogenous synthesis of lowermelting, nonessential acids. This phenomenon was not observed in cholesteryl esters or triacylglycerols. Nonesterified fatty acids showed significant changes in pattern of possible autacoid precursors. The abnormal profile of fatty acids in multiple sclerosis has features in common with prorfles of other syndromes involving viral infections.

Antioxidants and polyunsaturated fatty acids in multiple sclerosis

“…Nevertheless, there were deficiencies of essential PUFAs (ie PUFAs of the n-3 and n-6 series; Figure 1) in both plasma lipids and erythrocytes (Cherayil, 1984;Cunnane et al, 1989;Holman et al, 1989). Plasma linoleic acid (LA; 18:2n-6) was normal, and g-linolenic acid (GLA; 18:3n-6) increased in MS patients, but subsequent n-6 acids were subnormal, indicating impairment of chain elongation (Holman et al, 1989). In addition, the content of all n-3 fatty acids was subnormal and PUFA deficiency was compensated mass-wise by an increase in saturated fatty acids.…”

Alterations in the structure, physicochemical properties, and pH of hepatocyte lysosomes in experimental iron overload.

“…Results from the two groups of rats (control and iron overload) were compared using a two-sample independent t test with the Clinfo computer system. Fatty acid analyses were compared using normalcy ratios (19,20). P values of 0.05 or less were considered statistically significant.…”

“…Fatty acid methyl esters were extracted with petroleum ether and the percentage of individual fatty acids was determined with capillary gas chromatography using a bonded silica column (FFAP 2; Quadrex Corp., New Haven, CT). The double bond index was calculated by summing the products of mole fraction by number of double bonds per molecule for each fatty acid present in the sample (20).…”

Gas Chromatography Results Interpretation: Absolute Amounts Versus Relative Percentages

“…The n-6 and n-3 polyunsaturated fatty acids, C18:2n-6, C20:4n-6 and C20:5n-3 have been reported to be decreased in plasma and blood cell membranes from these patients (Baker et al, 1964;Cherayil, 1984;Holman et al, 1989;Nightingale et al, 1990;Hon et al, 2009aHon et al, , 2009b, but other research groups have found no differences compared to control subjects (Cumings et al, 1965;Fisher et al, 1987;Evans & Dodd, 1989;Koch et al, 2006). Disturbed metabolic relationships between C18:2n-6 and C20:3n-6 (Harbige & Sharief, 2007), as well as between C20:3n-6 and C20:4n-6 (Harbige & Sharief, 2007;Hon et al, 2009b) in the peripheral blood mononuclear cell membranes from patients with multiple sclerosis have also been reported.…”