Back to Search
Start Over
Growth hormone secretion and leptin in morbid obesity before and after biliopancreatic diversion: relationships with insulin and body composition
- Source :
- The Journal of clinical endocrinology and metabolism. 89(1)
- Publication Year :
- 2004
-
Abstract
- Obesity is characterized by increased leptin levels and insulin resistance, whereas blunted GH secretion is paired with normal, low, or high plasma IGF-I levels. To investigate body composition in human obesity and the interactions among the GH-IGF-I axis, leptin, and insulin resistance [measured with the homeostasis model assessment (HOMA) score], we studied 15 obese females, aged 23-54 yr (mean age, 42.7 +/- 2.6), with a body mass index (BMI) of 44.02 +/- 1.45 kg/m(2), who underwent treatment by biliopancreatic diversion (BPD), before and after surgery (16-24 months; BMI, 28.29 +/- 0.89 kg/m(2)). Our controls were 15 normal females, aged 28-54 yr (mean age, 40.8 +/- 2.3 yr), with a BMI of 27.52 +/- 0.53 kg/m(2). Insulin and leptin levels and HOMA scores were higher pre-BPD than in the controls. The GH response to GHRH was blunted, with a GH peak and GH area under the curve (AUC) significantly lower than those in controls. IGF-I and IGF-binding protein-3 (IGFBP-3) were also lower than control values. After surgery, BMI, fat mass, lean body mass, HOMA, insulin, and leptin significantly decreased. Furthermore, the GH response to GHRH severely increased; IGF-I and IGFBP-3 levels did not significantly vary. Considering all subjects, correlation analysis showed a strong positive correlation between insulin and leptin, and a negative correlation between insulin and GH peak and between insulin and GH AUC. Regression analysis performed grouping pre- and post-BPD indicated that leptin and GH peak or AUC could best be predicted from insulin levels. The surgical treatment of severe obesity after stabilization of body weight decreases BMI and fat mass while preserving normal lean body mass as well as positively influencing insulin sensitivity and thus aiding the normalization of leptin levels. The insulin reduction may be mainly involved in the increase in the GH response to GHRH through various possible central and peripheral mechanisms while decreasing the peripheral sensitivity to GH itself, as shown by the stable nature of the IGF-I and IGFBP-3 values. Our findings suggest that the changes in insulin levels are the starting point for changes in both leptin levels and the somatotrope axis after BPD.
- Subjects :
- Adult
Leptin
medicine.medical_specialty
Endocrinology, Diabetes and Metabolism
medicine.medical_treatment
Clinical Biochemistry
Growth Hormone-Releasing Hormone
Biochemistry
Body Mass Index
Insulin-like growth factor
Endocrinology
Insulin resistance
Internal medicine
medicine
Homeostasis
Humans
Insulin
Insulin-Like Growth Factor I
Pancreatic hormone
business.industry
Human Growth Hormone
Biochemistry (medical)
Middle Aged
medicine.disease
Biliopancreatic Diversion
Obesity
Growth hormone secretion
Obesity, Morbid
Insulin-Like Growth Factor Binding Protein 3
Adipose Tissue
Body Composition
Regression Analysis
Female
Insulin Resistance
business
Body mass index
Subjects
Details
- ISSN :
- 0021972X
- Volume :
- 89
- Issue :
- 1
- Database :
- OpenAIRE
- Journal :
- The Journal of clinical endocrinology and metabolism
- Accession number :
- edsair.doi.dedup.....a86a6c482aa01fb1c6e6a40a6bccf2ec