Effect of low-dose of recombinant human growth hormone on bone metabolism in elderly women with osteoporosis.
BACKGROUND
There has been increasing evidence that the growth hormone (GH)-IGF-I axis plays an important part in the maintenance of bone mass. However, controversy still exists as to the effect of GH treatment on bone mineral density (BMD) in elderly patients with osteoporosis.


OBJECTIVE
To investigate the effect of low-dose GH treatment on markers of body composition and bone turnover, serum concentrations of IGF-I and IGF-binding proteins (IGFBPs), and BMD at the radius and lumbar spine in eight elderly Japanese women with osteoporosis.


METHODS
Participants were treated with GH as a single daily subcutaneous injection (0.125 IU/kg per week; 0.00595 mg/kg per day) for 48 weeks.


RESULTS
Markers of bone formation and bone resorption were both increased up to 24 weeks of GH treatment. The bone formation markers remained increased during GH treatment, whereas the bone resorption markers returned to baseline values after 24 weeks of GH treatment. GH treatment caused a rapid (within 2 weeks) and sustained increase in serum IGF-I concentration. As for IGFBPs, serum concentrations of IGFBPs-2, -3 and -4 did not change significantly during GH treatment. In contrast, GH treatment caused a gradual increase in serum IGFBP-5 concentration, with a significant increase seen 48 weeks after the start of GH treatment. Radial BMD seemed to be increased during the late period of GH treatment, although the change was not significant. Lumbar BMD did not change during GH treatment. GH treatment caused a significant increase in hand grip strength. None of the GH-treated participants had new fractures and side effects such as edema and joint pain. Radial BMD was significantly increased after discontinuation of GH treatment for another 48 weeks and a similar tendency was observed at the lumbar spine (7.1+/-2.3% above pretreatment values for the radius and 3.6+/-2.0% for the lumbar spine).


CONCLUSIONS
Low-dose GH treatment attenuated the decrease in muscle strength and bone mass in elderly women without side effects, although changes in nutrition and exercise might affect BMD. The present findings provide useful information regarding the use of low-dose GH treatment in elderly women with osteoporosis.
Sugimoto
Toshitsugu
T
Division of Endocrinology/Metabolism, Neurology and Hematology/Oncology, Department of Clinical Molecular Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan. sugimot@med.kobe-u.ac.jp
Kaji
Hiroshi
H
Nakaoka
Daiki
D
Yamauchi
Mika
M
Yano
Shozo
S
Sugishita
Takeshi
T
Baylink
David J
DJ
Mohan
Subburaman
S
Chihara
Kazuo
K
D000368:Aged; D000469:Alkaline Phosphatase / Q000097:blood; D015415:Biomarkers / Q000097:blood; D001823:Body Composition; D001824:Body Constitution; D015519:Bone Density; D016723:Bone Remodeling; D001842:Bone and Bones / Q000187:drug effects* / Q000378:metabolism*; D002117:Calcitriol / Q000097:blood; D002118:Calcium / Q000097:blood; D003402:Creatine Kinase / Q000097:blood; D005260:Female; D018737:Hand Strength; D019382:Human Growth Hormone / Q000008:administration & dosage*; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood; D018975:Insulin-Like Growth Factor Binding Protein 5 / Q000097:blood; D018969:Insulin-Like Growth Factor Binding Proteins / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D007700:Kinetics; D008159:Lumbar Vertebrae; D010024:Osteoporosis / Q000188:drug therapy* / Q000378:metabolism; D010281:Parathyroid Hormone / Q000097:blood; D010710:Phosphates / Q000097:blood; D011884:Radius
D015415:Biomarkers; D018972:Insulin-Like Growth Factor Binding Protein 3; D018975:Insulin-Like Growth Factor Binding Protein 5; D018969:Insulin-Like Growth Factor Binding Proteins; D010281:Parathyroid Hormone; D010710:Phosphates; D019382:Human Growth Hormone; D007334:Insulin-Like Growth Factor I; D003402:Creatine Kinase; D000469:Alkaline Phosphatase; D002117:Calcitriol; D002118:Calcium