Effect of growth hormone replacement therapy on plasma lecithin:cholesterol acyltransferase and lipid transfer protein activities in growth hormone-deficient adults.
The effects of growth hormone (GH) replacement on plasma lecithin:cholesterol acyltransferase (LCAT), cholesteryl ester transfer protein (CETP), and phospholipid transfer protein (PLTP), factors involved in high density lipoprotein (HDL) metabolism, are unknown. We carried out a 6 months study in 24 GH-deficient adults who were randomized to placebo (n = 8), low dose GH (1 U daily, n = 8), and high dose GH (2 U daily, n = 8), followed by a 6 months open extension study with high dose GH (1 drop-out). No significant changes in plasma lipoproteins, LCAT, CETP, and PLTP activities, cholesterol esterification (EST) and cholesteryl ester transfer (CET) were observed after placebo. After 6 months of GH (combined data, n = 24), very low + low density lipoprotein (VLDL + LDL) cholesterol (P < 0.05) and apolipoprotein B (P < 0.05) decreased, whereas HDL cholesterol and HDL cholesteryl ester increased (P < 0. 05). Prolonged treatment showed comparable effects. Plasma apolipoprotein A-I and Lp[a] remained unchanged. Plasma LCAT (P < 0. 01) and CETP activities (P < 0.01), as well as EST (P < 0.01) and CET decreased (P < 0.01) after 12 months of GH (n = 15), but PLTP activity did not significantly change. Changes in EST and CET after 12 months of treatment were independently related to changes in plasma LCAT (P = 0.001 and CETP activity (P = 0.01). In conclusion, GH replacement therapy improves the lipoprotein profile in GH-deficient adults. Chronic GH replacement lowers plasma LCAT and CETP activities, contributing to a decrease in cholesterol esterification and cholesteryl ester transfer. These effects may have consequences for HDL metabolism and reverse cholesterol transport.
Beentjes
J A
JA
Department of Endocrinology, Cardiovascular Research Institute (COEUR), Erasmus University Rotterdam, The Netherlands.
van Tol
A
A
Sluiter
W J
WJ
Dullaart
R P
RP
D000328:Adult; D001692:Biological Transport; D002352:Carrier Proteins / Q000097:blood*; D002784:Cholesterol / Q000097:blood / Q000145:classification; D053480:Cholesterol Ester Transfer Proteins; D003677:Deficiency Diseases / Q000097:blood* / Q000188:drug therapy; D006023:Glycoproteins; D013006:Growth Hormone / Q000172:deficiency / Q000627:therapeutic use*; D006801:Humans; D008875:Middle Aged; D007862:Phosphatidylcholine-Sterol O-Acyltransferase / Q000097:blood*; D010919:Placebos
C506642:CETP protein, human; D002352:Carrier Proteins; D053480:Cholesterol Ester Transfer Proteins; D006023:Glycoproteins; D010919:Placebos; D013006:Growth Hormone; D002784:Cholesterol; D007862:Phosphatidylcholine-Sterol O-Acyltransferase