17-BETA-ESTRADIOL IMPROVES POSTPRANDIAL LIPID-METABOLISM IN POSTMENOPAUSAL WOMEN

We studied the effect of 2 mg micronized 17 beta-estradiol replacement therapy, administered orally during 6 weeks, on postprandial lipid an d retinyl palmitate (RP) metabolism. In the human postprandial state, atherogenic chylomicron remnant particles are produced. RP is incorpor ated into the core of newly synthesized chylomicrons and can be used a s a marker of chylomicrons and chylomicron remnants. Six normolipidemi c (plasma cholesterol, 5.63 +/- 0.83 mmol/L; plasma triglycerides, 1.4 7 +/- 0.69 mmol/L) postmenopausal women (amenorrhea >1 yr; aged 55.5 /- 4.0 yr) received an oral fat load (50 g/m(2) fat as cream, with 60. 000 IU RP/m(2)) before and after 6 weeks of 17 beta-estradiol treatmen t. Plasma RP areas under the curve decreased significantly from 27.1 /- 15.9 to 16.6 +/- 13.2 mg/h.L(-1) (P = 0.01). Pasting cholesterol co ncentrations in intermediate density Lipoproteins decreased significan tly. Fasting and postprandial plasma triglyceride levels did not chang e. These findings indicated that 17 beta-estradiol improved the postpr andial elimination of potentially atherogenic lipoprotein remnants.