STIMULATION OF THE APO AI HIGH-DENSITY-LIPOPROTEIN SYSTEM BY DIETARY SOYBEAN LECITHIN IN HUMANS

The aim of this work was to assess, the effect of a dietary supplement of soyabean lecithin on the apoprotein (apo) AI-high density lipoprot ein system in humans. Adult outpatients (three women and seven men, ag ed 52 +/- 5 years) were selected on the basis of a major type IIA hype rcholesterolemia (>6.5 mmol/L). For each subject, a previous control p eriod of 6 weeks consisted in a daily dietary supplement of 3 g soyabe an oil (SO) as placebo distributed in two capsules at three main meals . Subjects then were given a daily dietary supplement of 3 g purified soyabean phosphatidylcholine (SPC) for 6 weeks, also distributed in tw o capsules at the three main meals. The usual basal diet of each subje ct was monitored every 4 weeks by a 3-day food recall. Between the end of the SO period and the end of the SPC period, plasma level of apo A I significantly increased (from 1.01 to 1.23 gn), as did unesterified cholesterol (from 1.80 to 2.00 mmol/L). The esterified cholesterol to total cholesterol ratio and apo E level significantly decreased betwee n the beginning and the end of the experiment Esterified cholesterol a nd apo B levels remained unchanged. The levels of apo AI or unesterifi ed cholesterol were not correlated to the alcoholic calories or to tot al or lipid energy. Dietary soyabean lecithin contributed to stimulati on of the reverse cholesterol transport by increasing apo AI system an d decreasing apo AII and; apo E systems. Thus, soyabean lecithin could be considered an effective nutrient useful in the dietary treatment o f mild hypercholesterolemia. (C) Elsevier Science Inc. 1998.