CHOLESTERYL ESTER TRANSFER DURING POSTPRANDIAL LIPEMIA - THE EFFECT OF THE TYPE OF FAT IN THE MEAL

Background and Aim: To compare the effect of liquid meal of different fatty acid composition on the postprandial response of plasma newly sy nthesized cholesteryl ester transfer (NCET) activity, plasma cholester ol esterification rate (CER) and lathosterol concentration (an index o f cholesterol synthesis) in 18 healthy subjects. Methods and Results: The meals were rich in polyunsaturated fatty acids (PUFA), monounsatur ated fatty acids (MUFA) or coconut fat and dairy fat combined (COD). P lasma NCET activity increased in parallel with triglyceride (TG) conce ntration during the initial 200 minutes and remained elevated while tr iglycerides returned almost to baseline levels at 300 minutes after th e oral fat loads. Postprandial plasma CER increased after meals rich i n PUFA (P=0.018) and MUFA but did not change significantly after inges tion of COD. After meals rich in PUFA or MUFA, plasma NCET activity te nded to parallel plasma free cholesterol concentration during the ensu ing 300 minutes. Significantly smaller postprandial increases in plasm a NCET activity (p=0.038), plasma TG (p=0.002) and free cholesterol (p =0.029) concentrations were observed after the meal rich in COD compar ed with other meals. The increase in plasma NCET was correlated signif icantly (p<0.006) with the corresponding increases in free cholesterol and TG at 200 minutes after an oral load of PUFA or MUFA. Plasma NCET activity after meals rich in COD or MUFA, was significantly higher in subjects in the highest tertile of reported habitual dietary long cha in saturated fatty acid (SAFA) intake compared with other levels of in take. Plasma lathosterol concentration tended to decrease (p=0.06) dur ing the postprandial period and this change was not significantly infl uenced by the type of fat in the meal. Conclusions: The present data s uggest that meals rich in coconut fat give smaller postprandial increa ses in plasma TG levels and NCET activity than other types of fat and this may tend to conserve postprandial HDL cholesterol levels. (C)1998 , Medikal Press.