In missed abortion the decrease of IGF-1 down-regulates PI3K/AKT signaling pathway reducing the secretion of progesterone and β-hCG

Abstract

Objective

To explore whether the reduction of IGF-1 in missed abortion down-regulates PI3K/AKT signaling pathway, thereby causing trophoblast cell apoptosis and reducing the secretion of β-hCG and progesterone.

Design

12 pairs of serum and villous tissues were selected from missed abortion patients and normal early pregnant women who had terminated pregnancy by artificial abortion. The subjects in two groups had same age and gestational week. Wes Simple Western system and qRT-PCR were used to detect the expression of IGF-1, IGF-1R, PI3K/AKT signaling pathway and apoptosis-related factors in villous tissues. Radioimmunoassay and Enzyme-linked immunosorbent assay were used to detect β-hCG, progesterone and IGF-1 in serum.

Results

The serum levels of β-hCG, progesterone and IGF-1 were decreased in missed abortion group than those in normal early pregnant women. In addition, compared with normal early pregnant women, the genes and proteins levels of IGF-1 and PI3K/AKT signaling pathway and anti-apoptosis related factors were significantly decreased.

Conclusions

Our results suggested that the reduction of IGF-1 in missed abortion patients could down-regulate the expression of PI3K/AKT signaling pathway, thereby increasing the apoptosis of trophoblast cells, leading to decreased secretion of β-hCG and progesterone, which may be one of the important mechanisms of missed abortion.