IGF-II expression and methylation in small for gestational age infants

Area of Science:

• Endocrinology
• Genetics
• Neonatal Health

Background:

• Low birth weight is a risk factor for adult diseases.
• Investigated Insulin-like Growth Factor II (IGF-II) expression and differentially methylated regions (DMR) in small for gestational age (SGA) infants.

Purpose of the Study:

• To examine the relationship between birth weight and IGF-II expression and methylation patterns.
• To understand the role of IGF-II and H19 DMR in SGA infants.

Main Methods:

• Measured plasma levels of IGF-II, IGF2R, IGF-I, and IGFBP3 in 150 newborns.
• Quantified IGF2 mRNA and H19 mRNA using quantitative PCR.
• Assessed H19 and IGF2 DMR methylation status via methylation-specific PCR (MSP).

Main Results:

• Lower plasma IGF-II levels were observed in term SGA and large for gestational age (LGA) infants compared to appropriate for gestational age (AGA) infants.
• IGF2 mRNA expression was higher in term SGA than preterm SGA infants.
• H19 DMR methylation levels were elevated in both term SGA and LGA infants versus term AGA infants.

Conclusions:

• IGF-II is associated with birth weight and shows high postnatal expression, suggesting continued importance.
• H19 DMR methylation may play a role in regulating IGF-II expression postnatally.