Insulin-like Growth Factor Binding Proteins(IGFBPs) Profiles in CordSera of Appropriate-for gestational Age, Small-for-gestational Age,Large-for-gestational Age Infant and Preterm Infant / 대한산부인과학회잡지

ABSTRACT

The insulin-like growth factor(IGF) system consists of IGFs, their receptor and binding proteins(IGFBPs). The IGFs are important growth factors in the regulation of fetal growth. Since IGFBPs control IGF actions, the IGFBPs themselves may also be important in fetal growth and development. The goals of this study are to investigate the profiles of IGFBPs in cord sera of appropriate-for-gestatinal age(AGA, n=27), small-for-gestatinal age(SGA, n=14), large-for-gestatinal age(LGA, n=10) infants and preterm(PT, n=14) infants and to evaluate the relationship between these IGFBP levels and gestational weeks and birth weight and between total IGFBP levels in cord sera and paired maternal sera(n=65). The IGFBPs were analyzed by Western ligand blot and immunoprecipitation. In cord sera of AGA infants IGFBPs with molecular weight with 37/43 kilocatons(kDa; IGFBP-3), 31 kDa(IGFBP-2), 26 kDa(IGFBP-1), 24 kDa(IGFBP-4) were detected. In cord sera of LGA infants there was a significant increase in IGFBP-3 levels and a reduction of IGFBP-1 and IGFBP-4 levels compared with those in AGA infants. SGA infants had significantly higher IGFBP-1 and IGFBP-2 levels in cord sera than AGA infants. There was a similiar trend in IGFBP-1 levels in cord sera of PT infants. The relative proportion of IGFBP-4 in cord sera of SGA and PT infants was significantly higher than that of AGA infants. There was no significant correlation beween total IGFBP levels in cord sera and paired maternal sera. The ratios of total IGFBP in cord sera to that in maternal sera to that in maternal sera were significantly higher in SGA and PT infants than in AGA infants. The IGFBP-1 and IGFBP-2 levels correlated with birth weight but did not correlate with gestational weeks. These data suggest that there is an unique profile of IGFBPs in cord sera of infants according to their weight, and that IGFBPs may play a major role in the control of fetal growth.