THE IMPORTANCE OF DIETARY EICOSAPENTAENOIC TO DOCOSAHEXAENOIC ACID RATIO IN MODULATION OF SERUM-LIPID AND ARACHIDONIC-ACID LEVELS

The effect of feeding diets varying in eicosapentaenoic/docosahexaenoi c (EPA/DHA) acid ratio on serum cholesterol, triacylglycerol and fatty acyl chain composition was determined. Male Sprague-Dawley rats were fed EPA or DHA enriched diets and their serum lipid levels and fatty a cid profiles compared with those fed diets rich in saturated fatty aci ds (BT) or linoleic acid (SFO). Both the EPA and DHA enriched diets lo wered cholesterol content in the serum to the same degree. Serum total cholesterol to HDL-cholesterol ratio was reduced by EPA rich diet whi le DHA enriched diet had no effect. Both the diets enriched with omega -3 fatty acids lowered serum triacylglycerol level. Although statistic ally insignificant, the DHA rich diet had a tendency to lower triacylg lycerol more efficiently than EPA. The serum arachidonic acid (AA) con tent was reduced by EPA enriched diet only, not by DHA. The fatty acid composition of phospholipid, triacylglycerol, and cholesteryl ester f ractions of serum lipids was affected differently by the EPA and DHA e nriched diets. These results suggest that the dietary ratio of EPA/DHA may be an important determinant of the lipid-lowering and anti-thromb otic potential of different marine oils.