Serum levels of insulin-like growth factor-I and insulin-like growth factor binding protein-3 in children with insulin-dependent diabetes mellitus.

Abstract

Pubertal development has recently been evaluated from the standpoint of changes in insulin-like growth factor (IGF)-I and IGF-binding protein-3 (IGFBP-3) levels in healthy children. We studied puberty related changes in serum IGF-I and IGFBP-3 levels in 24 patients (11 prepubertal) with insulin dependent diabetes mellitus (IDDM) and 26 healthy subjects (14 prepubertal). Serum IGF-I and IGFBP-3 levels were assayed using immunoradiometric assays and radioimmunoassays, respectively. Serum IGF-I and IGFBP-3 levels in diabetics did not increase during puberty, as opposed to those in healthy children. Serum IGF-I and IGFBP-3 levels of diabetic patients were found to be lower than those of control subjects during puberty (p < 0.0001 and p < 0.05, respectively). Proteolysis is believed to be a general mechanism to increase IGF bioavailability in the presence of IGFBPs. Increased IGFBP-3 protease activity has been shown in sera of children with IDDM as well as a decrease in this activity in response to insulin therapy. Our data displaying low IGFBP-3 levels in diabetic children may be due to increased proteolysis, which also causes a shift in IGF-I to its lower molecular weight forms. Higher rate of clearance of the latter may be the reason for the low IGF-I levels we observed in children with IDDM. The moderate correlation between insulin dose and IGFBP-3 levels (r = 0.5, p < 0.01) may suggest insulin to be a contributing factor in the regulation of IGFBP-3 levels. We conclude that regulation of IGF-I and IGFBP-3 concentrations is disturbed in children with IDDM, in particular during adolescence.

• Authors: P Cinaz, M Kendirci, S Kurtoglu, N Gökçora, N Buyan, I Yavuz, A Demir
• Journal: Journal of pediatric endocrinology & metabolism : JPEM (J Pediatr Endocrinol Metab) 1996 Jul-Aug Vol. 9 Issue 4 Pg. 475-82 ISSN: 0334-018X [Print] Germany
• PMID: 8910817 (Publication Type: Journal Article)

Chemical References

• Insulin
• Insulin-Like Growth Factor Binding Protein 3
• Insulin-Like Growth Factor I

Topics

• Adolescent
• Body Height
• Child
• Child, Preschool
• Diabetes Mellitus, Type 1 (blood, drug therapy)
• Female
• Humans
• Insulin (administration & dosage)
• Insulin-Like Growth Factor Binding Protein 3 (blood)
• Insulin-Like Growth Factor I (metabolism)
• Male
• Puberty (physiology)
• Reference Values