Effects of growth hormone and/or testosterone on very low density lipoprotein apolipoprotein B100 kinetics and plasma lipids in healthy elderly men: a randomised controlled trial.

Author(s): Giannoulis MG, Jackson N, Shojaee-Moradie F, Sonksen PH, Martin FC, Umpleby AM

Affiliation(s): Department of Diabetes and Endocrinology, St. Thomas's Hospital, GKT School of Medicine, King's College London, SE1 7EH, United Kingdom.

Publication date & source: 2006-10, Growth Horm IGF Res., 16(5-6):308-17. Epub 2006 Oct 9.

Publication type: Randomized Controlled Trial; Research Support, Non-U.S. Gov't

OBJECTIVE: To assess the effects of low dose recombinant growth hormone (GH), testosterone (T) and combined GH and T, on lipid profiles and very low density lipoprotein apolipoprotein B (VLDL apoB) metabolism. DESIGN AND PATIENTS: Sixty-nine healthy elderly men (65-80 yr) were studied in a six month double-blind, placebo-controlled trial. Participants were randomised to placebo GH and placebo T (P), GH and placebo T (GH), T and placebo GH (T) or GH and T (GHT). MEASUREMENTS: Plasma lipid profiles were assessed before treatment and at 6 months. VLDL apoB absolute secretion rate (ASR) and fractional catabolic rate (FCR) were measured in a subset of 21 men: P (n=5); GH (n=5); T (n=6); GHT (n=5), with an infusion of 1-(13)C leucine. Fat mass (FM) was measured by DEXA and intra-abdominal fat (IAF) by CT scan. RESULTS: IGF-I levels increased in the GH and GHT (P<0.001) groups: testosterone increased in the T (P=0.029) and GHT (P=0.05) groups. There was no change in total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, apolipoprotein A-I, apolipoprotein B or lipoprotein(a) in the GH, GHT or T groups. In the subset of 21 men, IGF-I levels increased similarly with GH and GHT (P<0.01) but T levels increased only with T (P<0.03). FM and IAF decreased significantly only with GHT (P<0.01, P=0.01). Treatment with GH, T or GHT had no effect on VLDL apoB ASR or VLDL FCR. CONCLUSION: Co-administration of GH and T in near physiological doses in healthy elderly men resulted in favourable changes in body composition without altering the plasma lipid profile or VLDL apoB metabolism.