Essential phospholipids modify immunological functions and reduce experimental atherosclerosis in rabbits

Atherosclerosis was induced in male mongrel rabbits with a high-fat diet and the influence of essential phospholipids (EPL) on plaque formation, parameters of lipid metabolism and immunological functions was studied. When EPL were added to the high-fat diet there was a significant reduction in the area of atherosclerotic involvement of the aorta. The serum concentration of lipids decreased, often to normal values, and cholesterol esterified with polyunsaturated fatty acids appeared. Normalization of the malonyldialdehyde level in plasma was accompanied by a decrease in the concentration of ascorbate free radicals in blood and liver. The high-fat diet caused a depression of both non-specific and specific immune functions studied. With EPL in the diet the tests showed near normal or normal values. It is inferred from these results that a normal state of the immune system is important for preventing the progress of atherosclerotic changes. This is discussed with reference to the role of some immune cells in the metabolism of lipids and to participation of essential phospholipids in plasma membrane functions.