Comparative effects of feeding different fats on fatty acid composition of major individual phospholipids of rat hearts

Comparative effects of feeding dietary linoleic (corn oil), oleic (olive oil), alpha-linolenic (soybean oil) and polyunsaturated fatty acids (fish oil) on lipid content and fatty acid composition of major individual phospholipids of rat hearts were examined. Feeding different diets did not result in lipid accumulation in the heart. Total triglyceride, nonesterified fatty acid, cholesteryl ester and phospholipid levels of heart tissue were not affected by the type of dietary fatty acid. However, heart free cholesterol levels decreased in both animals fed the olive and the fish oil diets. The percentage of individual phospholipids, phosphatidylcholine (PC), phosphatidylethanolamine (PE) and cardiolipin (CL) did not modify by changes in the dietary fat composition. Heart tissue from animals fed on olive oil were enriched with 18:1 (n-9 + n-7) fatty acid in all phospholipid fractions. Animals fed corn oil contained higher proportions of 18:2 (n-6) for PC, PE and CL, and the ingestion of the soybean oil diet increased 18:2 (n-6) for PC and CL in the same proportion as the ingestion of the corn oil diet. The levels of 22:6 (n-3) were increased in the fish oil-fed group, accompanied by both a decrease in total (n-6) fatty acids and an increase in total (n-3) fatty acids in the three phospholipid fractions. The 20:5 (n-3) was only detected in these animals. These results show that olive oil is as effective as fish oil in reducing heart cholesterol content and support earlier works suggesting the role of fish oil in preventing cardiovascular disease.