Linoleic acid enrichment of serum phosphatidylcholine in humans by low doses of sodium linoleate.

Fifteen volunteers were treated daily during a week with 250 mg of sodium linoleate supply as suppository. A day before and a day after treatment venous blood samples were drawn, high density lipoproteins (HDL) fractionated and 3-sn phosphatidylcholine isolated by thin-layer chromatography from total serum and HDL and their fatty acid composition analyzed by gas-liquid chromatography. The positional esterification of linoleic acid in the phosphatidylcholine molecule was determined by enzymatic hydrolysis. Increases of linoleic acid of 1.8--136.3% in the serum phosphatidylcholine were observed in 14 out of 15 volunteers and an increment of 6.3--32.2% was also detected in the lipid fraction from HDL. In both fractions about 98% of the linoleic acid is located in the C2 position of the phosphatidylcholine molecule. The results reported in the present paper show that it is possible to promote the enrichment of linoleic acid in the phosphatidylcholine fractions of both serum and HDL from humans subjected to low doses of sodium linoleate supply as suppository.