Serum Levels of Adiponectin and IGFBP-1 in Short Children Born Small for Gestational Age
Posted 04/04/2007
Tomohiro Kamoda; Hiroki Nozue; Akira Matsui
Author Information
Summary and Introduction
Summary
Objective: The aim of this study was to quantify serum adiponectin concentrations in short children born small for gestational age (SGA) compared with those in children born appropriate for gestational age (AGA), and to assess the relationship between the serum levels of adiponectin and insulin-like growth factor binding protein-1 (IGFBP-1) known as a predictor of the development of type 2 diabetes mellitus and cardiovascular disease.
Subjects and Methods: Sixteen prepubertal short children born SGA and 20 short children born AGA, matched for age, body mass index, height, pubertal status, gestational age, bone age and midparental height, were included in the study. The serum levels of adiponectin, IGFBP-1, insulin and insulin-like growth factor-I (IGF-I) were measured in the fasting state.
Results: The levels of serum adiponectin were significantly lower in the SGA than in AGA children (10·5 ± 4·2 vs. 13·9 ± 5·1 µg/ml, P < 0·05). The levels of serum IGFBP-1, insulin and IGF-I were all similar in both groups. Overall, there was a significant positive correlation between adiponectin and IGFBP-1 (r = 0·40, P < 0·05).
Conclusions: Our results suggest that hypoadiponectinaemia in short SGA children without catch-up growth may reflect insulin resistance and imply a higher risk of developing type 2 diabetes mellitus. Additionally, adiponectin may be a more sensitive indicator for latent insulin resistance than IGFBP-1 in short SGA children.
Introduction
Intrauterine growth retardation is associated with an increased risk of developing type 2 diabetes mellitus and cardiovascular disease later in life.[1,2] To explain this association, the concept of ‘reprogramming’ was introduced[3]: foetal adaptation to an adverse intrauterine environment determines altered programming of the endocrine pathways, leading to permanent metabolic changes, including insulin resistance. Some investigators have reported that small for gestational age (SGA) children develop an impaired insulin sensitivity compared to normal appropriate for gestational age (AGA) children.[4,5]
Adiponectin is a protein derived from adipose tissue in humans, and serum adiponectin levels are paradoxically reduced in obese individuals.[6] Decreased concentrations of adiponectin are also seen in patients with insulin resistance or type 2 diabetes mellitus.[7] The lower levels of adiponectin in SGA infants may imply the very early development of insulin resistance, as recently suggested in neonatal rats,[8] in older children born SGA,[4,5] and in adults born SGA.[9] On the other hand, insulin-like growth factor binding protein-1 (IGFBP-1) has been implicated in the development of cardiovascular disease and has been reported to be a useful marker for hyperinsulinaemia in obese individuals.[10] We have also reported that the serum IGFBP-1 level is suppressed in prepubertal obese children with fasting normoinsulinaemia, suggesting that the reduced IGFBP-1 level may reflect latent hyperinsulinaemia.[11] Although the suppressed IGFBP-1 levels by compensatory hyperinsulinaemia would be expected in SGA children, the IGFBP-1 levels in SGA individuals varied among the studies, with reduced[12] and similar levels[13] when compared with control subjects. To date, there have been no studies investigating the relationship between adiponectin and IGFBP-1 in SGA children. The aim of the present study was to determine the serum adiponectin and IGFBP-1 levels, and to assess the relationship between the two parameters in short SGA children.
physiology 