Markers of collagen metabolism and insulin-like growth factor binding protein-1 in term infants

Abstract

Aim - To study the relation between fetal growth and markers of collagen metabolism and insulin-like growth factor binding protein-1 (IGFBP-1) in term infants. Methods - Cord vein plasma was obtained from 67 term infants of gestational age 37.1-41.7 weeks (39 appropriate for gestational age (AGA), 11 large for gestational age (LGA; relative birth weight ≥ 2.0 SD), and 17 small for gestational age (SGA; relative birth weight ≤ -2.0 SD)) for analysis of markers of metabolism of collagen type I (PICP and ICTP) and III (PIIINP) and of IGFBP-1. Results - Negative correlations existed between gestational age and PICP (r = -0.294, p = 0.0158), ICTP (r = -0.338, p = 0.0052), and PIIINP (r = -0.432, p = 0.0003). These correlations were also found in SGA infants (all p < 0.05). IGFBP-1 showed negative correlations with birth weight and relative birth weight (r=-0.644, p = 0.0001, and r=- 0.693, p = 0.0001 respectively) but not with gestational age (p>0.05). Conclusions - In the term fetus, collagen metabolism is primarily dependent on maturity and not on intrauterine growth status, whereas IGFBP-1 reflects intrauterine growth independently of maturity.