EFFECT OF APOLIPOPROTEIN-E POLYMORPHISM ON SERUM-LIPOPROTEIN RESPONSETO SATURATED FATTY-ACIDS

This report summarizes two studies which investigated the effects of a polipoprotein E (apoE) polymorphism on the serum total cholesterol (TC ) and lipoprotein cholesterol responses to 8:0 + 10:0 and 12:0 diets ( Study I) and 14:0, 16:0, and 18:0 diets (Study II). Eighteen healthy p remenopausal women (3 apoE 3/2, 12 apoE 3/3, 3 apoE 4/3) in study I an d another 18 healthy premenopausal women (4 apoE 3/2, 10 apoE 3/3, 3 a poE 4/3, 1 apoE 4/2) in study II consumed a baseline diet providing 40 en% total fat, 11 en% 18:2, 15 en% 18:1, 11.5 en% saturated fat for t he first week of each 5-wk period. The experimental diets for both stu dies provided 40 en% total fat, 13-14 en% as one of five test saturate d fatty acids (SFA), 14-16 en% 18:1, and 3-4 en% 18:2. Analysis by apo E phenotypes showed that both the 8:0 + 10:0 diet and the 12:0 diet in Study I induced significant increases in serum TC in subjects with di fferent apoE phenotypes with the exception of apoE 3/2 in the medium-c hain triglyceride group. In contrast, in Study II, individuals with ap oE 4/3 consuming the 14:0 diet showed significant increases in serum T C, high density lipoprotein-cholesterol (HDL-C), and HDL2-C, but the s ame subjects consuming the 16:0 diet showed significant increases in s erum TC and low density lipoprotein-cholesterol The findings from both studies indicated serum lipoprotein responses to SFA were different a nd the variation of responsiveness may be regulated, at least in part, by apoE polymorphism, especially when 14:0, 16:0, or 18:0 was consume d.