Back to Search
Start Over
Body composition, fasting leptin, and sex steroid administration determine GH sensitivity in peripubertal short children.
- Source :
-
The Journal of clinical endocrinology and metabolism [J Clin Endocrinol Metab] 2001 Dec; Vol. 86 (12), pp. 5805-12. - Publication Year :
- 2001
-
Abstract
- Serum IGF-I levels in GH-treated subjects demonstrate a wide range of responsiveness to GH. However, the factors influencing GH sensitivity are not well known. The aim of this work was 1) to test whether body composition (determined by dual energy x-ray absorptiometry) or factors related to body composition (fasting blood glucose, FFA, C-peptide, leptin, and insulin sensitivity determined by an insulin tolerance test) influence GH sensitivity; and 2) to study the effect of sex steroid priming on GH sensitivity. We measured serum IGF-I at baseline and 24 h after a single administration of GH (2 mg/m(2)) in 60 healthy prepubertal and early pubertal children (height, -2.1 +/- 1.0 SD score). GH sensitivity, as estimated by the increase in serum IGF-I after GH administration (difference between stimulated and baseline serum IGF-I = delta IGF-I), was also determined after a short-term administration of oral ethinyl E2 in girls and im T in boys. The serum IGF-I concentration was 297 +/- 114 microg/liter at baseline and increased to 429 +/- 160 microg/liter, corresponding to a 46 +/- 29% increase over the baseline value (P < 0.0001, stimulated vs. baseline serum IGF-I). delta IGF-I was not different between gender or pubertal stage. There were positive correlations (P < 0.001) between delta IGF-I and adiposity (total body fat, r = 0.62; trunk fat, r = 0.62), fasting leptin (r = 0.64), and C-peptide (r = 0.54), and a negative correlation with fasting FFA (r = -0.33; P < 0.05) even after adjustment for age, gender, and pubertal stage. These factors remained significant independent predictors of the absolute as well as the percent increase in serum IGF-I in multiple regression analyses. Priming with T and ethinyl E2 had a similar stimulating effect on the serum GH peak in response to the insulin tolerance test. In boys, serum baseline IGF-I increased by 60%, and delta IGF-I was similar after vs. before T administration. By contrast, in girls, serum baseline IGF-I was similar, and delta IGF-I was 60% less after vs. before ethinyl E2 administration. This study indicates that 1) GH sensitivity is determined by fat mass, serum fasting leptin, C-peptide, and FFA; and 2) oral ethinyl E2 and im T have divergent effects on the IGF-I response to a single administration of GH.
- Subjects :
- Adolescent
Body Height
Child
Ethinyl Estradiol therapeutic use
Female
Forecasting
Growth Disorders drug therapy
Growth Disorders pathology
Human Growth Hormone therapeutic use
Humans
Insulin physiology
Insulin-Like Growth Factor I metabolism
Male
Recombinant Proteins therapeutic use
Sex Characteristics
Testosterone therapeutic use
Body Composition physiology
Fasting blood
Gonadal Steroid Hormones therapeutic use
Growth Disorders physiopathology
Human Growth Hormone physiology
Leptin blood
Puberty physiology
Subjects
Details
- Language :
- English
- ISSN :
- 0021-972X
- Volume :
- 86
- Issue :
- 12
- Database :
- MEDLINE
- Journal :
- The Journal of clinical endocrinology and metabolism
- Publication Type :
- Academic Journal
- Accession number :
- 11739442
- Full Text :
- https://doi.org/10.1210/jcem.86.12.8095