Short- and long-term effects of human growth hormone HGH replacement on protein metabolism in HGH-deficient adults.
Shi J - J Clin Endocrinol Metab - 01-DEC-2003; 88(12): 5827-33
From NIH/NLM MEDLINE
NLM Citation ID:
14671176 (PubMed)
Full Source Title:
Journal of Clinical Endocrinology and Metabolism
Publication Type:
Journal Article
Language:
English
Author Affiliation:
Department of Medicine, Children's Nutrition Research Center, Baylor College of Medicine, Houston, Texas 77030, USA.
Authors:
Shi J; Sekhar RV; Balasubramanyam A; Ellis K; Reeds PJ; Jahoor F; Sharma MD
Abstract:
Reduced fat-free mass (FFM) in HGH-deficient (HGHD) adults is improved by HGH replacement, but the protein metabolic changes are unclear. Using iv [(2)H(3)]leucine and oral l-[(13)C(1)]leucine infusions and dual emission x-ray absorptiometry, we compared leucine kinetics and body composition in eight GHD adults and eight healthy controls in the fasted and fed states, before and after 2 wk and 6 months of GH replacement. Leucine kinetics were not different between pretreatment GHD subjects and controls. After 2 wk of HGH treatment, leucine oxidation decreased in the GHD subjects compared with baseline values [fasted, 41 +/- 6 vs. 30 +/- 5 micromol/kg FFM.h (P < 0.01); fed, 49 +/- 3 vs. 41 +/- 3.6 micromol/kg FFM.h (P < 0.05)], leucine balance improved [fasted, -14 +/- 4 vs. -3.5 +/- 3 micromol/kg FFM.h (P < 0.01); fed, 65 +/- 10 vs. 72 +/- 7 micromol/kg FFM.h (P = 0.07)], and protein synthesis increased [fasted, 116 +/- 5 vs. 131 +/- 6 micromol/kg FFM.h (P < 0.05); fed, 103 +/- 6 vs. 116 +/- 6 micromol/kg FFM.h (P < 0.05)]. After 6 months of GH treatment, these changes were not maintained in the fed state. The five HGHD subjects with decreased FFM at baseline showed a significant increase after 6 months of HGH treatment (P < 0.05). HGH replacement in HGHD acutely improves protein balance by stimulating synthesis and inhibiting catabolism. After 6 months, protein kinetics reached a new homeostasis to maintain the net gain in FFM.
Major Subjects:
- Human Growth Hormone / * deficiency
- Leucine / metabolism / * pharmacokinetics
Additional Subjects:
- Adult
- Aged
- Body Composition / drug effects
- Case-Control Studies
- Fasting / metabolism
- Female
- Homeostasis
- Humans
- Male
- Metabolism, Inborn Errors / metabolism
- Middle Aged
- Oxidation-Reduction / drug effects
- Research Support, Non-U.S. Gov't
- Research Support, U.S. Gov't, Non-P.H.S.
- Research Support, U.S. Gov't, P.H.S.
- Time Factors
Chemical Compound Name:
12629-01-5(Human Growth Hormone); 61-90-5(Leucine)