Analysis of total lipid extracts from human liver by C-13 and H-1 nuclear magnetic resonance spectroscopy

Lipid extracts of liver tissue from normal donors and from patients with acute liver failure were analyzed by C-13 NMR and H-1 NMR at 9.4 T. The spectra allowed estimation of (i) the free fatty acid to total fatty acid chains ratio, (ii) the polyunsaturated to monounsaturated lipids ratio, (iii) the glycerophospholipids to triacylglycerols ratio, (iv) the total cholesterol to total fatty acids molar ratio, (v) the acylcholesterol to cholesterol ratio, (vi) the phosphatidylcholine to phosphatidylethanolamine molar ratio, and (vii) the unsaturation ratio of the fatty acid chains. The values obtained for normal livers agree with literature data on lipid composition obtained by other techniques. The two pathologic livers differ from the normal in the composition of some lipids and show a higher free fatty acid to total fatty acid chains ratio and a lower polyunsaturated to monounsaturated lipid ratio, a lower acylcholesterol to cholesterol ratio, and a lower phosphatidylcholine to phosphatidylethanolamine ratio, whereas the ratio of total cholesterol to fatty acids and the unsaturation ratio remained unchanged, The detailed assignment of the C-13 NMR spectra of lipid extracts from normal and pathologic human liver may contribute to direct future research programs on C-13 NMR spatially localized spectroscopy of the liver in vivo. (C) 1996 Academic Press, Inc.