Associations between IGF-I, IGF-binding proteins and bone turnover markers in prepubertal obese children

Area of Science:

• Pediatric Endocrinology
• Bone Metabolism
• Obesity Research

Background:

• Childhood obesity is a growing concern with potential impacts on skeletal development.
• The growth hormone axis plays a role in both growth and metabolic regulation.

Purpose of the Study:

• To investigate the associations between the growth hormone axis, body composition, and bone turnover markers in obese children.
• To explore potential predictors of bone health in prepubertal obese individuals.

Main Methods:

• Assessed bone alkaline phosphatase (BALP), C-terminal telopeptide of type I collagen (CTX-I), insulin-like growth factor-I (IGF-I), and IGF-binding proteins (IGFBPs) using immunoenzymatic assays.
• Determined body composition via dual-energy X-ray absorptiometry in 45 obese and 20 non-obese children.

Main Results:

• Obese children exhibited significantly higher IGF-I and functional IGFBP-3 levels, as well as elevated IGF-I/total IGFBP-3 and functional IGFBP-3/total IGFBP-3 molar ratios compared to controls.
• Multivariate regression revealed significant associations between BALP and both IGF-I (p=0.047) and percent body fat mass (p=0.002) in obese subjects.

Conclusions:

• Findings suggest that IGF-I and functional IGFBP-3 may influence accelerated bone formation in obese children.
• IGF-I and percentage of body fat mass emerge as significant predictors of BALP in prepubertal obese children, highlighting their role in bone health.