Cholesteryl ester tranfer protein (CETP) and lecithin: Cholesterol acyltransferase (LCAT) activities in postmenopausal women exercise and hormone replacement therapy (HRT) effects

This study compared CETP and LCAT activities in post-menopausal women not undergoing HRT nor doing exercise (CNT group), those undergoing HRT and those doing aerobic endurance exercise 3 days/wk, one h/day during a 6 month period (EXE group). Participants were 55-70 years old (10 CNT, 12 HRT and 10 EXE). Values for plasma total and HDL cholesterol and CETP and LCAT activities were calculated from the mean of two samples taken at different times to adjust for variability within subjects. There was a strong correlation between plasma total and HDL cholesterol of samples measured day 1 versus day 2 which was taken 7-14 days later (r = 0.86 and 0.91, respectively, P < 0.001) Plasma total and HDL cholesterol were not different among groups. Values were 209 ± 24, 211 ± 38 and 209 ± 22 for total and 53 ± 14, 50 ± 9 and 57 ± 16 for HDL in the CNT, HRT and EXE groups respectively. Plasma LCAT activity expressed as μg/ml-h was higher in the EXE group (26.9 ± 7.4) compared to CNT group (21.2 ± 4.6) (P < 0.05) and the HRT group had an intermediate value (25.3 ± 7.0) not different from either group. CETP activities did not differ among groups (14.6 ± 4.5, 15.5 ± 3.1 and 13.8 ± 5.2 μg/ml-h). These studies suggest that although differences were not observed on plasma HDL cholesterol values among groups, exercise favors cholesterol esterification in HDL through LCAT activity improving reverse cholesterol transport in postmenopausal women.