Related Experiment Videos
Insulin-like growth factor I, insulin-like growth factor binding proteins, and growth hormone binding protein in
1Autonomous University, Hospital of Niño Jesús, Division of Pediatric Endocrinology, Madrid, Spain.
Insights
This study establishes normal reference values for insulin-like growth factor I (IGF-I), IGF-binding proteins (IGFBP-1, IGFBP-3), and growth hormone binding protein (GHBP) in newborns. Premature infants show lower levels, highlighting the role of IGFBPs in fetal development.
Area of Science:
- Pediatric Endocrinology
- Neonatology
- Growth Factor Biology
Background:
- Normal reference ranges for key growth-related proteins are not well-established in large newborn cohorts.
- Understanding these values is crucial for assessing infant growth and development.
Purpose of the Study:
- To establish normative data for IGF-I, IGFBP-1, IGFBP-3, and GHBP in healthy full-term newborns.
- To compare these values with those in premature infants and healthy prepubertal children.
- To investigate the relationship between these parameters and gestational age, ponderal index, and developmental stage.
Main Methods:
- Serum samples were collected from 271 Spanish full-term newborns, 39 premature infants, and 252 prepubertal children.
- Levels of IGF-I, IGFBP-1, IGFBP-3, and GHBP were measured using established assays.
- Statistical analyses, including ANOVA and Student's t-test, were employed to compare groups and assess correlations.
Main Results:
- Serum GHBP, IGF-I, and IGFBP-3 levels were significantly lower in premature infants compared to full-term newborns, increasing with gestational age.
- IGFBP-1 levels showed a negative correlation with gestational age.
- A direct relationship was observed between ponderal index and IGF-I and IGFBP-3 levels.
Conclusions:
- This study provides essential normative data for IGF-I, IGFBP-1, IGFBP-3, and GHBP in full-term newborns.
- Findings indicate that IGFBPs play a significant role in modulating IGF-I action during fetal development.
- The data supports the transition of growth factor profiles from fetal to childhood stages.
Abstract:
The normal values of insulin-like growth factor I (IGF-I), IGF-binding proteins 1 and 3 (IGFBP-1 and IGFBP-3), and the high-affinity growth hormone binding protein (GHBP) are not well established in large series of healthy fullterm newborns. We report the normative data for IGF-I, IGFBP-I, IGFBP-3, and GHBP in 271 normal Spanish full-term newborns, born between 37 and 42 weeks of gestation, and compare these results with the same parameters studied in 39 premature infants. Furthermore, we report the relationship between results found in the normal full-term newborns and those of 252 healthy prepubertal (Tanner stage I) Spanish children. Serum GHBP, IGF-I, and IGFBP-3 levels are very low in the premature infant and show a significant increase in full-term newborns, and continue to decline during childhood (p < 0.001; analysis of variance). A positive correlation between GHBP, IGF-I, and IGFBP-3 versus gestational age was observed. In contrast, we found a negative correlation between IGFBP-I and gestational age. There is a direct relationship between the ponderal index and IGF-I and IGFBP-3. When the group of premature newborns was divided into infants born before or after 32 weeks of gestation, we found higher levels of IGF-I and IGFBP-3 (p < 0.01 and p < 0.05, respectively, by Student's test) in the group with the higher gestational age; however, the IGFBP-I level was lower in this group (p < 0.001 by Student's t test), with no differences seen in serum GHBP concentrations. The presence of IGFBPs in the premature infant suggests that they are important modulators of IGF-I action during fetal growth and development.