SERUM LEVELS OF INSULIN-LIKE GROWTH-FACTOR-I AND INSULIN-LIKE-GROWTH-FACTOR BINDING PROTEIN-3 IN OBESE CHILDREN

Growth hormone (GH) and insulin-like growth factor-I (IGF-I) metabolis m may be disturbed in obese children. We investigated serum GH, IGF-I, IGF-binding protein-3 (IGFBP-3) levels in 42 obese and 40 non-obese h ealthy children aged 6-14 years. GH stimulation tests with L-dopa and insulin were performed. Serum IGF-I levels were studied by immunoradio metric assay (IRMA) and IGFBP-3 levels by radioimmunoassay (RIA). IGF- I levels were significantly higher in the obese group (p < 0.05), but IGFBP-3 levels were not different from the control group. IGF-I and IG FBP-3 levels were significantly higher in the obese pubertal children than in the obese prepubertal ones (p < 0.05). A positive linear corre lation was found between body mass index (BMI) and IGF-I levels (r = 0 .51, p < 0.05). These results suggest that obesity may have a consider able effect on IGF-I.