In Vitro and in Vivo Effects of Inositol Phosphatide (Lipositol) Fraction of Soybean on Serum Lipids and Lipoproteins

¹ From the Medical Division, Montefiore Hospital, New York City

Previous in vitro studies have shown that the alcohol insoluble inositol phosphatide (lipositol) fraction of soybean phosphatide complex produces an increase in the electrophoretic migration velocity of serum lipoproteins, while the alcohol soluble lecithin fraction is without effect. Extension of these studies revealed that the increase in electrophoretic migration velocity of serum lipoproteins produced by addition of the lipositol fraction to serum was inhibited by the addition of protamine in vitro, but was not inhibited by heating to 56°C. Lipositol isolated from the alcohol-insoluble fraction was found to be the compound responsible for the observed effects. The in vitro effects on lipoproteins were confirmed in vivo by intravenous administration of the lipositol fraction to normal rabbits. These changes were not accompanied by an increase in clearing factor activity. In the normal rabbit the ‘lipoprotein shift’ is accompanied by a prompt and profound mobilization of neutral fat and cholesterol to the blood stream.