Kinetics of lipids, apolipoproteins, and cholesteryl ester transfer protein in plasma after a bicycle marathon

Abstract

The short-term effects of prolonged intense exercise on plasma lipid transport parameters including cholesterol, triglycerides (TGs), low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, and its subfractions HDL 2 cholesterol and HDL 3 cholesterol, on apolipoproteins (apos) A-I, A-II, and B, and on mass and activity of cholesteryl ester transfer protein (CETP) were studied in eight male endurance-trained athletes over the first week after a bicycle marathon. CETP mass concentration in plasma was quantified by a newly developed immunoradiometric assay (IRMA). Plasma concentrations of cholesterol, TGs, LDL cholesterol, apo B, CETP, and cholesteryl ester transfer activity (CETA) were significantly reduced in the recovery period compared with pre-exercise values (cholesterol by 20%, P < .05; TGs by 63%, P < .05; LDL cholesterol by 32%, P < .05; apo B by 18%, P < .05; CETP mass by 29%, P < .05; and CETA by 14%, P < .05). HDL cholesterol and HDL 2 cholesterol, in contrast, were significantly increased in the post-exercise period (HDL cholesterol by 12%, P < .05, and HDL 2 cholesterol by 96%, P < .05), whereas HDL 3 cholesterol showed a tendency to decrease in the late recovery period (by 8%, NS). Although changes in cholesterol, triglycerides, HDL cholesterol, LDL cholesterol, apo B, and CETP mass and activity were already evident in the early recovery period, HDL 2 cholesterol showed a delayed response, reaching its maximum 72 hours after initiation of exercise. In addition, significant increases in plasma levels of apo A-I and A-II were found 8 days after the marathon (by 5%, P < .05, and by 12%, P < .05, respectively). Our data suggest that even in highly trained athletes, universally favorable lipoprotein changes of unexpected quantity result from a single episode of heavy exertion. The sustained and pronounced increase of HDL 2 cholesterol may be explained at least in part by the decrease in CETP after short-term exercise.