Purpose: Insulin-like growth factor-1 plays an important role in fetal growth and development, and its level increases with gestational age. The latest reports show that IGF-1 can directly influence the production of VEGF and regulate the development of blood vessels. Thus, the aim of the study was to evaluate the plasma concentrations of IGF-1 and VEGF as well as analyze their mutual correlation in preterm infants with retinopathy of prematurity (ROP), compared with preterm infants without ROP and full-term babies.
Material and methods: To address this issue, peripheral blood samples (PB) were analyzed and collected 10 weeks after delivery from: 25 preterm infants with proliferative stage of retinopathy of prematurity (ROP) and neovascularization (stage 3 or more advanced), 25 preterm infants without ROP, and 25 healthy full-term control infants. Plasma concentrations of VEGF and IGF-1 were measured using high-sensitivity enzyme-linked immunosorbent assay (ELISA) kits.
Results: Increased concentrations of VEGF (p < 0.05), were found in the PB of the preterm infants with ROP compared with the preterm babies without retinopathy as well as with the full-term control infants, in whom the lowest levels of the growth factor were observed. The plasma concentrations of IGF-1 in the preterm infants were significantly lower than those of the full-term babies (p < 0.001). After adjustment for gestational age as a independent variable, a tendency to higher concentrations of IGF-1 was observed in the preterm infants with ROP.
Conclusions: Disturbances in the interactions of VEGF and IGF-1 at early stages of ROP, leading to uncontrolled increases in their levels in the proliferative phase of disease, can play an important role in the pathogenesis of retinopathy of prematurity.