Variations in the fatty acid composition of lipid classes from lipoproteins in elderly women

Fatty acid composition of lipid classes and NMR spectra of lipoproteins were compared in 6 young (24-35-year-old) and 6 elderly (79-90-year-old) women. Cholesteryl ester, triglyceride and protein content of LDL in elderly women were significantly higher (+52-57% and +20% for lipids and proteins, respectively) than those observed in young women. HDL lipid levels were similar in the two groups. The proportion of linoleic acid (mainly in cholesteryl esters and phospholipids) of each lipoprotein species was always lower in octogenarians when compared with young females (lowering of 13-28% and 27-46% for cholesteryl esters and phospholipids, respectively). Conversely, the proportions of mono-unsaturated fatty acids (mainly oleic acid) increased in all lipid classes, although this was only significant in cholesteryl esters from each lipoprotein species. NMR spectra of lipoproteins showed a restricted mobility of acyl chain terminal CH3 groups in old women which was significant only in VLDL and HDL3. This suggests that the decrease of linoleic acid could affect the lipid mobility in lipoproteins of elderly women.