EFFECT OF A SINGLE EXERCISE SESSION ON THE TIME COURSE OF REVERSE CHOLESTEROL TRANSPORT VARIABLES

Abstract

A single session of exercise has been known to elevate HDL-chol levels, probably through alterations in the variables of the Reverse Cholesterol Transport pathway (RCT). PURPOSE: To establish a time course of the changes in HDL-chol levels, LCAT and CETP activities in response to a single exercise session. METHODS: Subjects were 10 sedentary normolipidemic males (fasting TG = 127 ± 13 mg/dl (mean ± SE), age = 37 ± 2y, VO2max = 36 ± 2ml/kg/min, body fat = 23 ± 2%) and 6 hypertriglyceridemic males (HTG) (fasting TG-267 ± 35mg/dl, age = 41 ± 3y, VO2max = 28 ± 2ml/kg/min, body fat = 23 ± 2%). All subjects performed 4 trials: 4h-post exercise trial, 8h-post exercise trial, 12h-post exercise trial, 24h-post exercise trial. The exercise sessions consisted of 60 min jog a treadmill at 60% of the subject's VO2max. Blood samples were taken immediately prior to exercise and at the established time point for the trial. Pre- and post-exercise analysis of HDLt-chol, HDL2-chol, and LCAT and CETP activities were determined. RESULTS: A significant difference was observed between control and HTG groups for HDLt-chol (37.2 ± 1.9 vs 28.0 ± 0.9 mg/dl) and LCAT activity (3.0 ± 0.3 vs 5.6 ± 0.3% esterified/4h). There were no group differences for HDL2-chol or CETP activity. Significant pre- and post-exercise changes were found only for HDLt-chol (34.2 ± 1.9 vs 33.2 ± 1.9 mg/dl). There were no trial differences for all variables, HDLt-chol, HDL2-chol, LCAT or CETP. CONCLUSIONS: We did not see the expected increases in HDL-chol, this was most likely due to the completely sedentary population. The present study does support the previous findings of decreased HDLt-chol and increased LCAT activity in the HTG population. Funded by AHA grant 9960292Z.